###Selektiranje elemenata iz vektora  ----

WHO <- read.csv("WHO.csv") 
summary(WHO) #1.st quartile, (25%observation) #3rd quartilw 75%
##    Country             Region            Population         Under15     
##  Length:194         Length:194         Min.   :      1   Min.   :13.12  
##  Class :character   Class :character   1st Qu.:   1696   1st Qu.:18.72  
##  Mode  :character   Mode  :character   Median :   7790   Median :28.65  
##                                        Mean   :  36360   Mean   :28.73  
##                                        3rd Qu.:  24535   3rd Qu.:37.75  
##                                        Max.   :1390000   Max.   :49.99  
##                                                                         
##      Over60      FertilityRate   LifeExpectancy  ChildMortality   
##  Min.   : 0.81   Min.   :1.260   Min.   :47.00   Min.   :  2.200  
##  1st Qu.: 5.20   1st Qu.:1.835   1st Qu.:64.00   1st Qu.:  8.425  
##  Median : 8.53   Median :2.400   Median :72.50   Median : 18.600  
##  Mean   :11.16   Mean   :2.941   Mean   :70.01   Mean   : 36.149  
##  3rd Qu.:16.69   3rd Qu.:3.905   3rd Qu.:76.00   3rd Qu.: 55.975  
##  Max.   :31.92   Max.   :7.580   Max.   :83.00   Max.   :181.600  
##                  NA's   :11                                       
##  CellularSubscribers  LiteracyRate        GNI       
##  Min.   :  2.57      Min.   :31.10   Min.   :  340  
##  1st Qu.: 63.57      1st Qu.:71.60   1st Qu.: 2335  
##  Median : 97.75      Median :91.80   Median : 7870  
##  Mean   : 93.64      Mean   :83.71   Mean   :13321  
##  3rd Qu.:120.81      3rd Qu.:97.85   3rd Qu.:17558  
##  Max.   :196.41      Max.   :99.80   Max.   :86440  
##  NA's   :10          NA's   :91      NA's   :32     
##  PrimarySchoolEnrollmentMale PrimarySchoolEnrollmentFemale
##  Min.   : 37.20              Min.   : 32.50               
##  1st Qu.: 87.70              1st Qu.: 87.30               
##  Median : 94.70              Median : 95.10               
##  Mean   : 90.85              Mean   : 89.63               
##  3rd Qu.: 98.10              3rd Qu.: 97.90               
##  Max.   :100.00              Max.   :100.00               
##  NA's   :93                  NA's   :93
#Postoji nekoliko nacina da selektujemo vektor u osnovnom R paketu:  
#** prema poziciji 
#** prema vrijednosti
#** prema imenu 

#**Prema poziciji:----
WHO[5] #peta varijabla
##     Over60
## 1     3.82
## 2    14.93
## 3     7.17
## 4    22.86
## 5     3.84
## 6    12.35
## 7    14.97
## 8    14.06
## 9    19.46
## 10   23.52
## 11    8.24
## 12   11.24
## 13    3.38
## 14    6.89
## 15   15.78
## 16   19.31
## 17   23.81
## 18    5.74
## 19    4.54
## 20    6.90
## 21    7.28
## 22   20.52
## 23    5.63
## 24   10.81
## 25    7.03
## 26   26.11
## 27    3.88
## 28    3.87
## 29    7.67
## 30    4.89
## 31   20.82
## 32    7.05
## 33    5.74
## 34    3.80
## 35   13.80
## 36   13.42
## 37    9.19
## 38    4.50
## 39    5.13
## 40    9.07
## 41   10.15
## 42    5.10
## 43   24.69
## 44   17.95
## 45   16.92
## 46   23.23
## 47   12.74
## 48    4.51
## 49   23.90
## 50    5.96
## 51   12.35
## 52    8.97
## 53    9.21
## 54    8.62
## 55    9.64
## 56    4.53
## 57    3.73
## 58   23.92
## 59    5.17
## 60    8.38
## 61   25.90
## 62   23.82
## 63    7.38
## 64    3.72
## 65   19.47
## 66   26.72
## 67    5.40
## 68   25.41
## 69    9.72
## 70    6.56
## 71    5.03
## 72    5.06
## 73    5.18
## 74    6.70
## 75    6.41
## 76   23.41
## 77   17.62
## 78    8.10
## 79    7.86
## 80    7.82
## 81    4.95
## 82   16.59
## 83   15.15
## 84   26.97
## 85   10.98
## 86   31.92
## 87    5.30
## 88   10.04
## 89    4.25
## 90    8.84
## 91    3.80
## 92    6.34
## 93    5.76
## 94   24.24
## 95   12.03
## 96    6.31
## 97    4.76
## 98    6.96
## 99   20.57
## 100  19.15
## 101   4.45
## 102   4.92
## 103   8.21
## 104   6.65
## 105   4.29
## 106  22.87
## 107   8.84
## 108   4.94
## 109  13.23
## 110   9.18
## 111   6.67
## 112  23.82
## 113   5.80
## 114  18.58
## 115   7.61
## 116   5.01
## 117   8.15
## 118   5.38
## 119   8.84
## 120   7.65
## 121  23.02
## 122  19.01
## 123   6.59
## 124   4.26
## 125   4.49
## 126   9.07
## 127  21.41
## 128   3.99
## 129   6.44
## 130   8.84
## 131  10.13
## 132   4.79
## 133   8.01
## 134   9.12
## 135   6.21
## 136  20.48
## 137  24.39
## 138   1.73
## 139  16.58
## 140  16.72
## 141  20.66
## 142  18.60
## 143   3.94
## 144  12.35
## 145  12.13
## 146   9.92
## 147   7.39
## 148  26.97
## 149   4.76
## 150   4.59
## 151   4.57
## 152  20.52
## 153  10.05
## 154   4.41
## 155  15.13
## 156  18.60
## 157  23.16
## 158   5.10
## 159   4.46
## 160   8.44
## 161   5.26
## 162  22.86
## 163  12.40
## 164   4.99
## 165   9.55
## 166   5.34
## 167  25.32
## 168  23.25
## 169   6.09
## 170   4.80
## 171  13.96
## 172  17.56
## 173   5.16
## 174   4.44
## 175   7.96
## 176  13.18
## 177  10.49
## 178  10.56
## 179   6.30
## 180   9.07
## 181   3.72
## 182  20.76
## 183   0.81
## 184  23.06
## 185   4.89
## 186  19.31
## 187  18.59
## 188   6.38
## 189   6.02
## 190   9.17
## 191   9.32
## 192   4.54
## 193   3.95
## 194   5.68
WHO$Region[5] #peti element/obseracija u varijabli Region
## [1] "Africa"
WHO$Region[-5] #sve osim 5 elementa
##   [1] "Eastern Mediterranean" "Europe"                "Africa"               
##   [4] "Europe"                "Americas"              "Americas"             
##   [7] "Europe"                "Western Pacific"       "Europe"               
##  [10] "Europe"                "Americas"              "Eastern Mediterranean"
##  [13] "South-East Asia"       "Americas"              "Europe"               
##  [16] "Europe"                "Americas"              "Africa"               
##  [19] "South-East Asia"       "Americas"              "Europe"               
##  [22] "Africa"                "Americas"              "Western Pacific"      
##  [25] "Europe"                "Africa"                "Africa"               
##  [28] "Western Pacific"       "Africa"                "Americas"             
##  [31] "Africa"                "Africa"                "Africa"               
##  [34] "Americas"              "Western Pacific"       "Americas"             
##  [37] "Africa"                "Africa"                "Western Pacific"      
##  [40] "Americas"              "Africa"                "Europe"               
##  [43] "Americas"              "Europe"                "Europe"               
##  [46] "South-East Asia"       "Africa"                "Europe"               
##  [49] "Eastern Mediterranean" "Americas"              "Americas"             
##  [52] "Americas"              "Eastern Mediterranean" "Americas"             
##  [55] "Africa"                "Africa"                "Europe"               
##  [58] "Africa"                "Western Pacific"       "Europe"               
##  [61] "Europe"                "Africa"                "Africa"               
##  [64] "Europe"                "Europe"                "Africa"               
##  [67] "Europe"                "Americas"              "Americas"             
##  [70] "Africa"                "Africa"                "Americas"             
##  [73] "Americas"              "Americas"              "Europe"               
##  [76] "Europe"                "South-East Asia"       "South-East Asia"      
##  [79] "Eastern Mediterranean" "Eastern Mediterranean" "Europe"               
##  [82] "Europe"                "Europe"                "Americas"             
##  [85] "Western Pacific"       "Eastern Mediterranean" "Europe"               
##  [88] "Africa"                "Western Pacific"       "Eastern Mediterranean"
##  [91] "Europe"                "Western Pacific"       "Europe"               
##  [94] "Eastern Mediterranean" "Africa"                "Africa"               
##  [97] "Eastern Mediterranean" "Europe"                "Europe"               
## [100] "Africa"                "Africa"                "Western Pacific"      
## [103] "South-East Asia"       "Africa"                "Europe"               
## [106] "Western Pacific"       "Africa"                "Africa"               
## [109] "Americas"              "Western Pacific"       "Europe"               
## [112] "Western Pacific"       "Europe"                "Eastern Mediterranean"
## [115] "Africa"                "South-East Asia"       "Africa"               
## [118] "Western Pacific"       "South-East Asia"       "Europe"               
## [121] "Western Pacific"       "Americas"              "Africa"               
## [124] "Africa"                "Western Pacific"       "Europe"               
## [127] "Eastern Mediterranean" "Eastern Mediterranean" "Western Pacific"      
## [130] "Americas"              "Western Pacific"       "Americas"             
## [133] "Americas"              "Western Pacific"       "Europe"               
## [136] "Europe"                "Eastern Mediterranean" "Western Pacific"      
## [139] "Europe"                "Europe"                "Europe"               
## [142] "Africa"                "Americas"              "Americas"             
## [145] "Americas"              "Western Pacific"       "Europe"               
## [148] "Africa"                "Eastern Mediterranean" "Africa"               
## [151] "Europe"                "Africa"                "Africa"               
## [154] "Western Pacific"       "Europe"                "Europe"               
## [157] "Western Pacific"       "Eastern Mediterranean" "Africa"               
## [160] "Eastern Mediterranean" "Europe"                "South-East Asia"      
## [163] "Eastern Mediterranean" "Americas"              "Africa"               
## [166] "Europe"                "Europe"                "Eastern Mediterranean"
## [169] "Europe"                "South-East Asia"       "Europe"               
## [172] "South-East Asia"       "Africa"                "Western Pacific"      
## [175] "Americas"              "Eastern Mediterranean" "Europe"               
## [178] "Europe"                "Western Pacific"       "Africa"               
## [181] "Europe"                "Eastern Mediterranean" "Europe"               
## [184] "Africa"                "Americas"              "Americas"             
## [187] "Europe"                "Western Pacific"       "Americas"             
## [190] "Western Pacific"       "Eastern Mediterranean" "Africa"               
## [193] "Africa"
WHO$Region[5:10] # elemente od 5 do 10, ukljucujuci 5 i 10
## [1] "Africa"          "Americas"        "Americas"        "Europe"         
## [5] "Western Pacific" "Europe"
WHO[5:10] #kada ne stavimo zarez onda R podrazumjeva sve obzervacije i uzima komandu za varijable
##     Over60 FertilityRate LifeExpectancy ChildMortality CellularSubscribers
## 1     3.82          5.40             60           98.5               54.26
## 2    14.93          1.75             74           16.7               96.39
## 3     7.17          2.83             73           20.0               98.99
## 4    22.86            NA             82            3.2               75.49
## 5     3.84          6.10             51          163.5               48.38
## 6    12.35          2.12             75            9.9              196.41
## 7    14.97          2.20             76           14.2              134.92
## 8    14.06          1.74             71           16.4              103.57
## 9    19.46          1.89             82            4.9              108.34
## 10   23.52          1.44             81            4.0              154.78
## 11    8.24          1.96             71           35.2              108.75
## 12   11.24          1.90             75           16.9               86.06
## 13    3.38          2.12             79            9.6              127.96
## 14    6.89          2.24             70           40.9               56.06
## 15   15.78          1.84             78           18.4              127.01
## 16   19.31          1.47             71            5.2              111.88
## 17   23.81          1.85             80            4.2              116.61
## 18    5.74          2.76             74           18.3               69.96
## 19    4.54          5.01             57           89.5               85.33
## 20    6.90          2.32             67           44.6               65.58
## 21    7.28          3.31             67           41.4               82.82
## 22   20.52          1.26             76            6.7               84.52
## 23    5.63          2.71             66           53.3              142.82
## 24   10.81          1.82             74           14.4              124.26
## 25    7.03          2.03             77            8.0              109.17
## 26   26.11          1.51             74           12.1              140.68
## 27    3.88          5.78             56          102.4               45.27
## 28    3.87          6.21             53          104.3               22.33
## 29    7.67          2.93             65           39.7               96.17
## 30    4.89          4.94             53           94.9               52.35
## 31   20.82          1.66             82            5.3               79.73
## 32    7.05          2.38             72           22.2               79.19
## 33    5.74          4.54             48          128.6               40.65
## 34    3.80          6.49             51          149.8               31.80
## 35   13.80          1.84             79            9.1              129.71
## 36   13.42          1.66             76           14.0               73.19
## 37    9.19          2.35             78           17.6               98.45
## 38    4.50          4.85             62           77.6               28.71
## 39    5.13          5.05             58           96.0               93.84
## 40    9.07            NA             77           10.6                  NA
## 41   10.15          1.83             79            9.9               92.20
## 42    5.10          4.91             56          107.6               86.06
## 43   24.69          1.48             77            4.7              116.37
## 44   17.95          1.46             78            5.5               11.69
## 45   16.92          1.47             81            3.2               97.71
## 46   23.23          1.53             78            3.8              123.44
## 47   12.74          2.00             69           28.8                4.09
## 48    4.51          6.15             49          145.7               23.09
## 49   23.90          1.88             79            3.7              128.47
## 50    5.96          3.53             58           80.9               21.32
## 51   12.35            NA             74           12.6              164.02
## 52    8.97          2.55             73           27.1               87.22
## 53    9.21          2.62             76           23.3              104.55
## 54    8.62          2.85             73           21.0              101.08
## 55    9.64          2.24             72           15.9              133.54
## 56    4.53          5.04             54          100.3               59.15
## 57    3.73          4.88             61           51.8                4.47
## 58   23.92          1.62             76            3.6              138.98
## 59    5.17          4.77             60           68.3               16.67
## 60    8.38          2.64             70           22.4               83.72
## 61   25.90          1.85             81            2.9              166.02
## 62   23.82          1.98             82            4.1               94.79
## 63    7.38          4.18             62           62.0              117.32
## 64    3.72          5.79             58           72.9               78.89
## 65   19.47          1.82             72           19.9              102.31
## 66   26.72          1.40             81            4.1              132.30
## 67    5.40          3.99             64           72.0               84.78
## 68   25.41          1.51             81            4.8              106.48
## 69    9.72          2.22             74           13.5                  NA
## 70    6.56          3.91             69           32.0              140.38
## 71    5.03          5.09             55          101.2               44.02
## 72    5.06          5.05             50          129.1               56.18
## 73    5.18          2.64             63           35.2               69.94
## 74    6.70          3.28             63           75.6               41.49
## 75    6.41          3.10             74           22.9              103.97
## 76   23.41          1.38             75            6.2              117.30
## 77   17.62          2.11             82            2.3              106.08
## 78    8.10          2.53             65           56.3               72.00
## 79    7.86          2.40             69           31.0              103.09
## 80    7.82          1.91             73           17.6               74.93
## 81    4.95          4.15             69           34.4               78.12
## 82   16.59          2.00             81            4.0              108.41
## 83   15.15          2.92             82            4.2              121.66
## 84   26.97          1.45             82            3.8              157.93
## 85   10.98          2.31             75           16.8              108.12
## 86   31.92          1.39             83            3.0              104.95
## 87    5.30          3.39             74           19.1              118.20
## 88   10.04          2.52             67           18.7              155.74
## 89    4.25          4.54             60           72.9               67.49
## 90    8.84          3.01             67           59.9               13.64
## 91    3.80          2.65             80           11.0              175.09
## 92    6.34          3.03             69           26.6              116.40
## 93    5.76          3.20             68           71.8               87.16
## 94   24.24          1.57             74            8.7              102.94
## 95   12.03          1.50             74            9.3               78.65
## 96    6.31          3.15             50           99.6               56.17
## 97    4.76          4.95             59           74.8               49.17
## 98    6.96          2.47             65           15.4              155.70
## 99   20.57          1.49             74            5.4              151.30
## 100  19.15          1.65             82            2.2              148.27
## 101   4.45          4.59             66           58.2               40.65
## 102   4.92          5.55             58           71.0               25.69
## 103   8.21          1.99             74            8.5              127.04
## 104   6.65          2.31             77           10.5              165.72
## 105   4.29          6.85             51          128.0               68.32
## 106  22.87          1.37             80            6.8              124.86
## 107   8.84            NA             60           37.9                  NA
## 108   4.94          4.78             59           84.0               93.60
## 109  13.23          1.51             74           15.1               99.04
## 110   9.18          2.25             75           16.2               82.38
## 111   6.67          3.40             69           38.5                  NA
## 112  23.82            NA             82            3.8               89.73
## 113   5.80          2.45             68           27.5              105.08
## 114  18.58          1.69             76            5.9                  NA
## 115   7.61          2.65             72           31.1              113.26
## 116   5.01          5.34             53           89.7               32.83
## 117   8.15          1.98             65           52.3                2.57
## 118   5.38          3.17             65           38.7               96.39
## 119   8.84            NA             71           37.1               65.00
## 120   7.65          2.50             68           41.6               43.81
## 121  23.02          1.76             81            4.1                  NA
## 122  19.01          2.10             81            5.7              109.19
## 123   6.59          2.59             73           24.4               82.15
## 124   4.26          7.58             56          113.5               29.52
## 125   4.49          6.02             53          123.7               58.58
## 126   9.07            NA             72           25.1                  NA
## 127  21.41          1.93             81            2.8              115.62
## 128   3.99          2.90             72           11.6              168.97
## 129   6.44          3.35             67           85.9               61.61
## 130   8.84            NA             72           20.8               74.94
## 131  10.13          2.52             77           18.5              188.60
## 132   4.79          3.90             63           63.0               34.22
## 133   8.01          2.93             75           22.0               99.40
## 134   9.12          2.48             77           18.2              110.41
## 135   6.21          3.11             69           29.8               99.30
## 136  20.48          1.39             76            5.0              130.97
## 137  24.39          1.33             80            3.6              115.39
## 138   1.73          2.06             82            7.4              123.11
## 139  16.58          1.29             81            3.8              108.50
## 140  16.72          1.47             71           17.6              104.80
## 141  20.66          1.39             74           12.2              109.16
## 142  18.60          1.51             69           10.3              179.31
## 143   3.94          4.73             60           55.0               40.63
## 144  12.35            NA             74            9.2                  NA
## 145  12.13          1.96             75           17.5              123.00
## 146   9.92          2.05             74           23.4              120.52
## 147   7.39          4.28             73           17.8                  NA
## 148  26.97            NA             83            3.3              111.75
## 149   4.76          4.22             63           53.2               68.26
## 150   4.59          2.76             76            8.6              191.24
## 151   4.57          5.02             61           59.6               73.25
## 152  20.52          1.37             74            6.6              125.39
## 153  10.05          2.23             74           13.1              145.71
## 154   4.41          4.86             47          181.6               35.63
## 155  15.13          1.27             82            2.9              150.24
## 156  18.60          1.37             76            7.5              109.35
## 157  23.16          1.49             80            3.1              106.56
## 158   5.10          4.17             70           31.1               49.77
## 159   4.46          6.77             50          147.4                6.85
## 160   8.44          2.44             58           44.6              126.83
## 161   5.26          5.10             54          104.0                  NA
## 162  22.86          1.47             82            4.5              113.22
## 163  12.40          2.35             75            9.6               87.05
## 164   4.99          4.56             62           73.1               56.14
## 165   9.55          2.32             72           20.8              178.88
## 166   5.34          3.48             50           79.7               63.70
## 167  25.32          1.93             82            2.9              118.57
## 168  23.25          1.51             83            4.3              131.43
## 169   6.09          3.04             75           15.1               63.17
## 170   4.80          3.81             68           58.3               90.64
## 171  13.96          1.43             74           13.2              111.63
## 172  17.56          1.44             75            7.4              107.24
## 173   5.16          6.11             64           56.7               53.23
## 174   4.44          4.75             56           95.5               50.45
## 175   7.96          3.86             72           12.8               52.63
## 176  13.18          1.80             71           20.7              135.64
## 177  10.49          2.04             76           16.1              116.93
## 178  10.56          2.08             76           14.2               88.70
## 179   6.30          2.38             63           52.8               68.77
## 180   9.07            NA             64           29.7               21.63
## 181   3.72          6.06             56           68.9               48.38
## 182  20.76          1.45             71           10.7              122.98
## 183   0.81          1.84             76            8.4              148.62
## 184  23.06          1.90             80            4.8              130.75
## 185   4.89          5.36             59           54.0               55.53
## 186  19.31          2.00             79            7.1               92.72
## 187  18.59          2.07             77            7.2              140.75
## 188   6.38          2.38             68           39.6               91.65
## 189   6.02          3.46             72           17.9               55.76
## 190   9.17          2.44             75           15.3               97.78
## 191   9.32          1.79             75           23.0              143.39
## 192   4.54          4.35             64           60.0               47.05
## 193   3.95          5.77             55           88.5               60.59
## 194   5.68          3.64             54           89.8               72.13
##     LiteracyRate
## 1             NA
## 2             NA
## 3             NA
## 4             NA
## 5           70.1
## 6           99.0
## 7           97.8
## 8           99.6
## 9             NA
## 10            NA
## 11            NA
## 12            NA
## 13          91.9
## 14          56.8
## 15            NA
## 16            NA
## 17            NA
## 18            NA
## 19          42.4
## 20            NA
## 21            NA
## 22          97.9
## 23          84.5
## 24            NA
## 25          95.2
## 26            NA
## 27            NA
## 28          67.2
## 29            NA
## 30            NA
## 31            NA
## 32          84.3
## 33          56.0
## 34          34.5
## 35            NA
## 36          94.3
## 37          93.4
## 38          74.9
## 39            NA
## 40            NA
## 41          96.2
## 42          56.2
## 43          98.8
## 44          99.8
## 45          98.3
## 46            NA
## 47            NA
## 48          66.8
## 49            NA
## 50            NA
## 51            NA
## 52          89.5
## 53          91.9
## 54          72.0
## 55          84.5
## 56          93.9
## 57          67.8
## 58          99.8
## 59            NA
## 60            NA
## 61            NA
## 62            NA
## 63          88.4
## 64          50.0
## 65          99.7
## 66            NA
## 67          67.3
## 68          97.2
## 69            NA
## 70          75.2
## 71          41.0
## 72          54.2
## 73            NA
## 74            NA
## 75          84.8
## 76          99.0
## 77            NA
## 78            NA
## 79            NA
## 80            NA
## 81          78.2
## 82            NA
## 83            NA
## 84          98.9
## 85          86.6
## 86            NA
## 87          92.6
## 88          99.7
## 89          87.4
## 90            NA
## 91            NA
## 92            NA
## 93            NA
## 94          99.8
## 95            NA
## 96          89.6
## 97          60.8
## 98          89.2
## 99          99.7
## 100           NA
## 101           NA
## 102         74.8
## 103         93.1
## 104           NA
## 105         31.1
## 106           NA
## 107           NA
## 108         58.0
## 109         88.5
## 110         93.1
## 111           NA
## 112           NA
## 113         97.4
## 114         98.4
## 115           NA
## 116         56.1
## 117         92.3
## 118         88.8
## 119           NA
## 120         60.3
## 121           NA
## 122           NA
## 123           NA
## 124           NA
## 125         61.3
## 126           NA
## 127           NA
## 128           NA
## 129           NA
## 130           NA
## 131         94.1
## 132         60.6
## 133         93.9
## 134           NA
## 135           NA
## 136         99.5
## 137         95.2
## 138         96.3
## 139           NA
## 140         98.5
## 141         97.7
## 142         99.6
## 143         71.1
## 144           NA
## 145           NA
## 146           NA
## 147         98.8
## 148           NA
## 149         89.2
## 150         86.6
## 151           NA
## 152         97.9
## 153         91.8
## 154         42.1
## 155         95.9
## 156           NA
## 157         99.7
## 158           NA
## 159           NA
## 160           NA
## 161           NA
## 162         97.7
## 163         91.2
## 164         71.1
## 165         94.7
## 166         87.4
## 167           NA
## 168           NA
## 169         83.4
## 170         99.7
## 171           NA
## 172         97.3
## 173         58.3
## 174           NA
## 175           NA
## 176         98.8
## 177           NA
## 178           NA
## 179         99.6
## 180           NA
## 181         73.2
## 182         99.7
## 183           NA
## 184           NA
## 185         73.2
## 186           NA
## 187         98.1
## 188         99.4
## 189         82.6
## 190           NA
## 191         93.2
## 192         63.9
## 193         71.2
## 194         92.2
WHO[c(1,5)] # prva i peta varijabla a sve obzervacije
##                                       Country Over60
## 1                                 Afghanistan   3.82
## 2                                     Albania  14.93
## 3                                     Algeria   7.17
## 4                                     Andorra  22.86
## 5                                      Angola   3.84
## 6                         Antigua and Barbuda  12.35
## 7                                   Argentina  14.97
## 8                                     Armenia  14.06
## 9                                   Australia  19.46
## 10                                    Austria  23.52
## 11                                 Azerbaijan   8.24
## 12                                    Bahamas  11.24
## 13                                    Bahrain   3.38
## 14                                 Bangladesh   6.89
## 15                                   Barbados  15.78
## 16                                    Belarus  19.31
## 17                                    Belgium  23.81
## 18                                     Belize   5.74
## 19                                      Benin   4.54
## 20                                     Bhutan   6.90
## 21           Bolivia (Plurinational State of)   7.28
## 22                     Bosnia and Herzegovina  20.52
## 23                                   Botswana   5.63
## 24                                     Brazil  10.81
## 25                          Brunei Darussalam   7.03
## 26                                   Bulgaria  26.11
## 27                               Burkina Faso   3.88
## 28                                    Burundi   3.87
## 29                                   Cambodia   7.67
## 30                                   Cameroon   4.89
## 31                                     Canada  20.82
## 32                                 Cape Verde   7.05
## 33                   Central African Republic   5.74
## 34                                       Chad   3.80
## 35                                      Chile  13.80
## 36                                      China  13.42
## 37                                   Colombia   9.19
## 38                                    Comoros   4.50
## 39                                      Congo   5.13
## 40                               Cook Islands   9.07
## 41                                 Costa Rica  10.15
## 42                                Ivory Coast   5.10
## 43                                    Croatia  24.69
## 44                                       Cuba  17.95
## 45                                     Cyprus  16.92
## 46                             Czech Republic  23.23
## 47      Democratic People's Republic of Korea  12.74
## 48           Democratic Republic of the Congo   4.51
## 49                                    Denmark  23.90
## 50                                   Djibouti   5.96
## 51                                   Dominica  12.35
## 52                         Dominican Republic   8.97
## 53                                    Ecuador   9.21
## 54                                      Egypt   8.62
## 55                                El Salvador   9.64
## 56                          Equatorial Guinea   4.53
## 57                                    Eritrea   3.73
## 58                                    Estonia  23.92
## 59                                   Ethiopia   5.17
## 60                                       Fiji   8.38
## 61                                    Finland  25.90
## 62                                     France  23.82
## 63                                      Gabon   7.38
## 64                                     Gambia   3.72
## 65                                    Georgia  19.47
## 66                                    Germany  26.72
## 67                                      Ghana   5.40
## 68                                     Greece  25.41
## 69                                    Grenada   9.72
## 70                                  Guatemala   6.56
## 71                                     Guinea   5.03
## 72                              Guinea-Bissau   5.06
## 73                                     Guyana   5.18
## 74                                      Haiti   6.70
## 75                                   Honduras   6.41
## 76                                    Hungary  23.41
## 77                                    Iceland  17.62
## 78                                      India   8.10
## 79                                  Indonesia   7.86
## 80                 Iran (Islamic Republic of)   7.82
## 81                                       Iraq   4.95
## 82                                    Ireland  16.59
## 83                                     Israel  15.15
## 84                                      Italy  26.97
## 85                                    Jamaica  10.98
## 86                                      Japan  31.92
## 87                                     Jordan   5.30
## 88                                 Kazakhstan  10.04
## 89                                      Kenya   4.25
## 90                                   Kiribati   8.84
## 91                                     Kuwait   3.80
## 92                                 Kyrgyzstan   6.34
## 93           Lao People's Democratic Republic   5.76
## 94                                     Latvia  24.24
## 95                                    Lebanon  12.03
## 96                                    Lesotho   6.31
## 97                                    Liberia   4.76
## 98                                      Libya   6.96
## 99                                  Lithuania  20.57
## 100                                Luxembourg  19.15
## 101                                Madagascar   4.45
## 102                                    Malawi   4.92
## 103                                  Malaysia   8.21
## 104                                  Maldives   6.65
## 105                                      Mali   4.29
## 106                                     Malta  22.87
## 107                          Marshall Islands   8.84
## 108                                Mauritania   4.94
## 109                                 Mauritius  13.23
## 110                                    Mexico   9.18
## 111          Micronesia (Federated States of)   6.67
## 112                                    Monaco  23.82
## 113                                  Mongolia   5.80
## 114                                Montenegro  18.58
## 115                                   Morocco   7.61
## 116                                Mozambique   5.01
## 117                                   Myanmar   8.15
## 118                                   Namibia   5.38
## 119                                     Nauru   8.84
## 120                                     Nepal   7.65
## 121                               Netherlands  23.02
## 122                               New Zealand  19.01
## 123                                 Nicaragua   6.59
## 124                                     Niger   4.26
## 125                                   Nigeria   4.49
## 126                                      Niue   9.07
## 127                                    Norway  21.41
## 128                                      Oman   3.99
## 129                                  Pakistan   6.44
## 130                                     Palau   8.84
## 131                                    Panama  10.13
## 132                          Papua New Guinea   4.79
## 133                                  Paraguay   8.01
## 134                                      Peru   9.12
## 135                               Philippines   6.21
## 136                                    Poland  20.48
## 137                                  Portugal  24.39
## 138                                     Qatar   1.73
## 139                         Republic of Korea  16.58
## 140                       Republic of Moldova  16.72
## 141                                   Romania  20.66
## 142                        Russian Federation  18.60
## 143                                    Rwanda   3.94
## 144                     Saint Kitts and Nevis  12.35
## 145                               Saint Lucia  12.13
## 146          Saint Vincent and the Grenadines   9.92
## 147                                     Samoa   7.39
## 148                                San Marino  26.97
## 149                     Sao Tome and Principe   4.76
## 150                              Saudi Arabia   4.59
## 151                                   Senegal   4.57
## 152                                    Serbia  20.52
## 153                                Seychelles  10.05
## 154                              Sierra Leone   4.41
## 155                                 Singapore  15.13
## 156                                  Slovakia  18.60
## 157                                  Slovenia  23.16
## 158                           Solomon Islands   5.10
## 159                                   Somalia   4.46
## 160                              South Africa   8.44
## 161                               South Sudan   5.26
## 162                                     Spain  22.86
## 163                                 Sri Lanka  12.40
## 164                                     Sudan   4.99
## 165                                  Suriname   9.55
## 166                                 Swaziland   5.34
## 167                                    Sweden  25.32
## 168                               Switzerland  23.25
## 169                      Syrian Arab Republic   6.09
## 170                                Tajikistan   4.80
## 171                                  Thailand  13.96
## 172 The former Yugoslav Republic of Macedonia  17.56
## 173                               Timor-Leste   5.16
## 174                                      Togo   4.44
## 175                                     Tonga   7.96
## 176                       Trinidad and Tobago  13.18
## 177                                   Tunisia  10.49
## 178                                    Turkey  10.56
## 179                              Turkmenistan   6.30
## 180                                    Tuvalu   9.07
## 181                                    Uganda   3.72
## 182                                   Ukraine  20.76
## 183                      United Arab Emirates   0.81
## 184                            United Kingdom  23.06
## 185               United Republic of Tanzania   4.89
## 186                  United States of America  19.31
## 187                                   Uruguay  18.59
## 188                                Uzbekistan   6.38
## 189                                   Vanuatu   6.02
## 190        Venezuela (Bolivarian Republic of)   9.17
## 191                                  Viet Nam   9.32
## 192                                     Yemen   4.54
## 193                                    Zambia   3.95
## 194                                  Zimbabwe   5.68
WHO[1:5,c(1,5)] #ovo je WHO[observacije,varijable] dakle lijevo od zareza biramo koje cemo redove, a desno koje cemo kolone
##       Country Over60
## 1 Afghanistan   3.82
## 2     Albania  14.93
## 3     Algeria   7.17
## 4     Andorra  22.86
## 5      Angola   3.84
#zadatak 1 -----   

#imajuci u vidu pravilo da je lijevo od zareza red a desno kolona kako da izlistate samo peti red (minuta)
# sacuvajte peti red baze WHO pod nazivom peti



#odgovor

WHO[5,]
##   Country Region Population Under15 Over60 FertilityRate LifeExpectancy
## 5  Angola Africa      20821   47.58   3.84           6.1             51
##   ChildMortality CellularSubscribers LiteracyRate  GNI
## 5          163.5               48.38         70.1 5230
##   PrimarySchoolEnrollmentMale PrimarySchoolEnrollmentFemale
## 5                        93.1                          78.2
peti <- WHO[5,]
peti
##   Country Region Population Under15 Over60 FertilityRate LifeExpectancy
## 5  Angola Africa      20821   47.58   3.84           6.1             51
##   ChildMortality CellularSubscribers LiteracyRate  GNI
## 5          163.5               48.38         70.1 5230
##   PrimarySchoolEnrollmentMale PrimarySchoolEnrollmentFemale
## 5                        93.1                          78.2
#**Prema vrijednosti  ----

WHO[WHO$Population > 650000,] #izdvaja samo one observacije koje su imaju populaciju vecu od 650hiljada 
##    Country          Region Population Under15 Over60 FertilityRate
## 36   China Western Pacific    1390000   17.95  13.42          1.66
## 78   India South-East Asia    1240000   29.43   8.10          2.53
##    LifeExpectancy ChildMortality CellularSubscribers LiteracyRate  GNI
## 36             76           14.0               73.19         94.3 8390
## 78             65           56.3               72.00           NA 3590
##    PrimarySchoolEnrollmentMale PrimarySchoolEnrollmentFemale
## 36                          NA                            NA
## 78                          NA                            NA
WHO[WHO$Over60 < 4,] #izdvaja samo one observacije koji su manji od 4
##                  Country                Region Population Under15 Over60
## 1            Afghanistan Eastern Mediterranean      29825   47.42   3.82
## 5                 Angola                Africa      20821   47.58   3.84
## 13               Bahrain Eastern Mediterranean       1318   20.16   3.38
## 27          Burkina Faso                Africa      16460   45.66   3.88
## 28               Burundi                Africa       9850   44.20   3.87
## 34                  Chad                Africa      12448   48.52   3.80
## 57               Eritrea                Africa       6131   43.10   3.73
## 64                Gambia                Africa       1791   45.90   3.72
## 91                Kuwait Eastern Mediterranean       3250   24.90   3.80
## 128                 Oman Eastern Mediterranean       3314   24.19   3.99
## 138                Qatar Eastern Mediterranean       2051   13.28   1.73
## 143               Rwanda                Africa      11458   43.56   3.94
## 181               Uganda                Africa      36346   48.54   3.72
## 183 United Arab Emirates Eastern Mediterranean       9206   14.41   0.81
## 193               Zambia                Africa      14075   46.73   3.95
##     FertilityRate LifeExpectancy ChildMortality CellularSubscribers
## 1            5.40             60           98.5               54.26
## 5            6.10             51          163.5               48.38
## 13           2.12             79            9.6              127.96
## 27           5.78             56          102.4               45.27
## 28           6.21             53          104.3               22.33
## 34           6.49             51          149.8               31.80
## 57           4.88             61           51.8                4.47
## 64           5.79             58           72.9               78.89
## 91           2.65             80           11.0              175.09
## 128          2.90             72           11.6              168.97
## 138          2.06             82            7.4              123.11
## 143          4.73             60           55.0               40.63
## 181          6.06             56           68.9               48.38
## 183          1.84             76            8.4              148.62
## 193          5.77             55           88.5               60.59
##     LiteracyRate   GNI PrimarySchoolEnrollmentMale
## 1             NA  1140                          NA
## 5           70.1  5230                        93.1
## 13          91.9    NA                          NA
## 27            NA  1300                        60.7
## 28          67.2   610                          NA
## 34          34.5  1360                          NA
## 57          67.8   580                        37.2
## 64          50.0  1750                        68.2
## 91            NA    NA                          NA
## 128           NA    NA                          NA
## 138         96.3 86440                        95.7
## 143         71.1  1270                          NA
## 181         73.2  1310                        89.7
## 183           NA 47890                          NA
## 193         71.2  1490                        91.4
##     PrimarySchoolEnrollmentFemale
## 1                              NA
## 5                            78.2
## 13                             NA
## 27                           55.9
## 28                             NA
## 34                             NA
## 57                           32.5
## 64                           70.4
## 91                             NA
## 128                            NA
## 138                          96.6
## 143                            NA
## 181                          92.3
## 183                            NA
## 193                          93.9
#**Prema imenu  ----

WHO [WHO$Region=="Europe",] #zarez je veoma bitan
##                                       Country Region Population Under15 Over60
## 2                                     Albania Europe       3162   21.33  14.93
## 4                                     Andorra Europe         78   15.20  22.86
## 8                                     Armenia Europe       2969   20.34  14.06
## 10                                    Austria Europe       8464   14.51  23.52
## 11                                 Azerbaijan Europe       9309   22.25   8.24
## 16                                    Belarus Europe       9405   15.10  19.31
## 17                                    Belgium Europe      11060   16.88  23.81
## 22                     Bosnia and Herzegovina Europe       3834   16.35  20.52
## 26                                   Bulgaria Europe       7278   13.53  26.11
## 43                                    Croatia Europe       4307   14.98  24.69
## 45                                     Cyprus Europe       1129   17.16  16.92
## 46                             Czech Republic Europe      10660   14.56  23.23
## 49                                    Denmark Europe       5598   17.66  23.90
## 58                                    Estonia Europe       1291   15.69  23.92
## 61                                    Finland Europe       5408   16.42  25.90
## 62                                     France Europe      63937   18.26  23.82
## 65                                    Georgia Europe       4358   17.62  19.47
## 66                                    Germany Europe      82800   13.17  26.72
## 68                                     Greece Europe      11125   14.60  25.41
## 76                                    Hungary Europe       9976   14.62  23.41
## 77                                    Iceland Europe        326   20.71  17.62
## 82                                    Ireland Europe       4576   21.54  16.59
## 83                                     Israel Europe       7644   27.53  15.15
## 84                                      Italy Europe      60885   14.04  26.97
## 88                                 Kazakhstan Europe      16271   25.46  10.04
## 92                                 Kyrgyzstan Europe       5474   30.21   6.34
## 94                                     Latvia Europe       2060   14.57  24.24
## 99                                  Lithuania Europe       3028   15.13  20.57
## 100                                Luxembourg Europe        524   17.46  19.15
## 106                                     Malta Europe        428   14.98  22.87
## 112                                    Monaco Europe         38   18.26  23.82
## 114                                Montenegro Europe        621   19.01  18.58
## 121                               Netherlands Europe      16714   17.21  23.02
## 127                                    Norway Europe       4994   18.64  21.41
## 136                                    Poland Europe      38211   14.91  20.48
## 137                                  Portugal Europe      10604   14.92  24.39
## 140                       Republic of Moldova Europe       3514   16.52  16.72
## 141                                   Romania Europe      21755   15.05  20.66
## 142                        Russian Federation Europe     143000   15.45  18.60
## 148                                San Marino Europe         31   14.04  26.97
## 152                                    Serbia Europe       9553   16.45  20.52
## 156                                  Slovakia Europe       5446   15.00  18.60
## 157                                  Slovenia Europe       2068   14.16  23.16
## 162                                     Spain Europe      46755   15.20  22.86
## 167                                    Sweden Europe       9511   16.71  25.32
## 168                               Switzerland Europe       7997   14.79  23.25
## 170                                Tajikistan Europe       8009   35.75   4.80
## 172 The former Yugoslav Republic of Macedonia Europe       2106   16.89  17.56
## 178                                    Turkey Europe      73997   26.00  10.56
## 179                              Turkmenistan Europe       5173   28.65   6.30
## 182                                   Ukraine Europe      45530   14.18  20.76
## 184                            United Kingdom Europe      62783   17.54  23.06
## 188                                Uzbekistan Europe      28541   28.90   6.38
##     FertilityRate LifeExpectancy ChildMortality CellularSubscribers
## 2            1.75             74           16.7               96.39
## 4              NA             82            3.2               75.49
## 8            1.74             71           16.4              103.57
## 10           1.44             81            4.0              154.78
## 11           1.96             71           35.2              108.75
## 16           1.47             71            5.2              111.88
## 17           1.85             80            4.2              116.61
## 22           1.26             76            6.7               84.52
## 26           1.51             74           12.1              140.68
## 43           1.48             77            4.7              116.37
## 45           1.47             81            3.2               97.71
## 46           1.53             78            3.8              123.44
## 49           1.88             79            3.7              128.47
## 58           1.62             76            3.6              138.98
## 61           1.85             81            2.9              166.02
## 62           1.98             82            4.1               94.79
## 65           1.82             72           19.9              102.31
## 66           1.40             81            4.1              132.30
## 68           1.51             81            4.8              106.48
## 76           1.38             75            6.2              117.30
## 77           2.11             82            2.3              106.08
## 82           2.00             81            4.0              108.41
## 83           2.92             82            4.2              121.66
## 84           1.45             82            3.8              157.93
## 88           2.52             67           18.7              155.74
## 92           3.03             69           26.6              116.40
## 94           1.57             74            8.7              102.94
## 99           1.49             74            5.4              151.30
## 100          1.65             82            2.2              148.27
## 106          1.37             80            6.8              124.86
## 112            NA             82            3.8               89.73
## 114          1.69             76            5.9                  NA
## 121          1.76             81            4.1                  NA
## 127          1.93             81            2.8              115.62
## 136          1.39             76            5.0              130.97
## 137          1.33             80            3.6              115.39
## 140          1.47             71           17.6              104.80
## 141          1.39             74           12.2              109.16
## 142          1.51             69           10.3              179.31
## 148            NA             83            3.3              111.75
## 152          1.37             74            6.6              125.39
## 156          1.37             76            7.5              109.35
## 157          1.49             80            3.1              106.56
## 162          1.47             82            4.5              113.22
## 167          1.93             82            2.9              118.57
## 168          1.51             83            4.3              131.43
## 170          3.81             68           58.3               90.64
## 172          1.44             75            7.4              107.24
## 178          2.08             76           14.2               88.70
## 179          2.38             63           52.8               68.77
## 182          1.45             71           10.7              122.98
## 184          1.90             80            4.8              130.75
## 188          2.38             68           39.6               91.65
##     LiteracyRate   GNI PrimarySchoolEnrollmentMale
## 2             NA  8820                          NA
## 4             NA    NA                        78.4
## 8           99.6  6100                          NA
## 10            NA 42050                          NA
## 11            NA  8960                        85.3
## 16            NA 14460                          NA
## 17            NA 39190                        98.9
## 22          97.9  9190                        86.5
## 26            NA 14160                        99.3
## 43          98.8 18760                        94.8
## 45          98.3    NA                        99.1
## 46            NA 24370                          NA
## 49            NA 41900                        94.8
## 58          99.8 20850                        97.7
## 61            NA 37670                        97.7
## 62            NA 35910                        99.1
## 65          99.7  5350                          NA
## 66            NA 40230                          NA
## 68          97.2 25100                        98.8
## 76          99.0 20310                        97.8
## 77            NA 31020                        98.8
## 82            NA 34180                        99.4
## 83            NA 27110                        97.0
## 84          98.9 32400                        99.6
## 88          99.7 11250                          NA
## 92            NA  2180                        95.5
## 94          99.8 17700                        95.0
## 99          99.7 19640                        95.6
## 100           NA 64260                        93.6
## 106           NA    NA                        93.3
## 112           NA    NA                          NA
## 114         98.4 13700                          NA
## 121           NA 43140                          NA
## 127           NA 61460                        99.1
## 136         99.5 20430                        96.9
## 137         95.2 24440                        99.1
## 140         98.5  3640                        90.1
## 141         97.7 15120                        87.9
## 142         99.6 20560                          NA
## 148           NA    NA                          NA
## 152         97.9 11540                        94.7
## 156           NA 22130                          NA
## 157         99.7 26510                        97.7
## 162         97.7 31400                        99.7
## 167           NA 42200                        99.7
## 168           NA 52570                        98.9
## 170         99.7  2300                        99.5
## 172         97.3 11090                        97.3
## 178           NA 16940                        99.5
## 179         99.6  8690                          NA
## 182         99.7  7040                        90.8
## 184           NA 36010                        99.8
## 188         99.4  3420                        93.3
##     PrimarySchoolEnrollmentFemale
## 2                              NA
## 4                            79.4
## 8                              NA
## 10                             NA
## 11                           84.1
## 16                             NA
## 17                           99.2
## 22                           88.4
## 26                           99.7
## 43                           97.0
## 45                           99.5
## 46                             NA
## 49                           96.9
## 58                           97.0
## 61                           97.9
## 62                           99.3
## 65                             NA
## 66                             NA
## 68                           99.3
## 76                           98.3
## 77                           99.2
## 82                          100.0
## 83                           97.8
## 84                           98.5
## 88                             NA
## 92                           95.1
## 94                           96.8
## 99                           95.8
## 100                          95.7
## 106                          94.3
## 112                            NA
## 114                            NA
## 121                            NA
## 127                          99.2
## 136                          96.7
## 137                          99.7
## 140                          90.1
## 141                          87.3
## 142                            NA
## 148                            NA
## 152                          94.4
## 156                            NA
## 157                          97.3
## 162                          99.8
## 167                          99.0
## 168                          99.5
## 170                          96.0
## 172                          99.2
## 178                          98.3
## 179                            NA
## 182                          91.5
## 184                          99.6
## 188                          91.0
##zadatak 5 minuta; ----
##ako je lijevo od zareza red a desno kolona, kako da opet dobijemo samo evropu ali za samo prvu, trecu i sestu varijablu?
##spasite kao WHOEurope







##odgovor
WHO [WHO$Region=="Europe",c(1,3,6)] #zarez je veoma bitan
##                                       Country Population FertilityRate
## 2                                     Albania       3162          1.75
## 4                                     Andorra         78            NA
## 8                                     Armenia       2969          1.74
## 10                                    Austria       8464          1.44
## 11                                 Azerbaijan       9309          1.96
## 16                                    Belarus       9405          1.47
## 17                                    Belgium      11060          1.85
## 22                     Bosnia and Herzegovina       3834          1.26
## 26                                   Bulgaria       7278          1.51
## 43                                    Croatia       4307          1.48
## 45                                     Cyprus       1129          1.47
## 46                             Czech Republic      10660          1.53
## 49                                    Denmark       5598          1.88
## 58                                    Estonia       1291          1.62
## 61                                    Finland       5408          1.85
## 62                                     France      63937          1.98
## 65                                    Georgia       4358          1.82
## 66                                    Germany      82800          1.40
## 68                                     Greece      11125          1.51
## 76                                    Hungary       9976          1.38
## 77                                    Iceland        326          2.11
## 82                                    Ireland       4576          2.00
## 83                                     Israel       7644          2.92
## 84                                      Italy      60885          1.45
## 88                                 Kazakhstan      16271          2.52
## 92                                 Kyrgyzstan       5474          3.03
## 94                                     Latvia       2060          1.57
## 99                                  Lithuania       3028          1.49
## 100                                Luxembourg        524          1.65
## 106                                     Malta        428          1.37
## 112                                    Monaco         38            NA
## 114                                Montenegro        621          1.69
## 121                               Netherlands      16714          1.76
## 127                                    Norway       4994          1.93
## 136                                    Poland      38211          1.39
## 137                                  Portugal      10604          1.33
## 140                       Republic of Moldova       3514          1.47
## 141                                   Romania      21755          1.39
## 142                        Russian Federation     143000          1.51
## 148                                San Marino         31            NA
## 152                                    Serbia       9553          1.37
## 156                                  Slovakia       5446          1.37
## 157                                  Slovenia       2068          1.49
## 162                                     Spain      46755          1.47
## 167                                    Sweden       9511          1.93
## 168                               Switzerland       7997          1.51
## 170                                Tajikistan       8009          3.81
## 172 The former Yugoslav Republic of Macedonia       2106          1.44
## 178                                    Turkey      73997          2.08
## 179                              Turkmenistan       5173          2.38
## 182                                   Ukraine      45530          1.45
## 184                            United Kingdom      62783          1.90
## 188                                Uzbekistan      28541          2.38
#sve ovo sto smo "selektirali" da bismo spasili moramo da ubacimo znak asign.
WHOEurope <- WHO [WHO$Region=="Europe",c(1,3,6)]

#podskup
WHO[WHO$Over60 %in% c(0.81,4.23,6.2,8),] #uzima samo elemente koji se nalaze u setu 0.81, 4.23, 6.2, 8. Buduci da samo Arab Emirati imaju udio stanovnistva starosti preko 60 jednak 0.81 samo je to i selektovano
##                  Country                Region Population Under15 Over60
## 183 United Arab Emirates Eastern Mediterranean       9206   14.41   0.81
##     FertilityRate LifeExpectancy ChildMortality CellularSubscribers
## 183          1.84             76            8.4              148.62
##     LiteracyRate   GNI PrimarySchoolEnrollmentMale
## 183           NA 47890                          NA
##     PrimarySchoolEnrollmentFemale
## 183                            NA
#ili da vidimo samo BiH
WHO[WHO$Country %in% c ("Bosnia and Herzegovina"),] #funkcija podskupa je veoma korisna ako imamo listu odredjenu koju zelimo "izvuci" iz orginalne baze.
##                   Country Region Population Under15 Over60 FertilityRate
## 22 Bosnia and Herzegovina Europe       3834   16.35  20.52          1.26
##    LifeExpectancy ChildMortality CellularSubscribers LiteracyRate  GNI
## 22             76            6.7               84.52         97.9 9190
##    PrimarySchoolEnrollmentMale PrimarySchoolEnrollmentFemale
## 22                        86.5                          88.4
#recimo zemlje iz razlicitog regiona: BiH, Oman, Egipat, Japan

WHO$Population
##   [1]   29825    3162   38482      78   20821      89   41087    2969   23050
##  [10]    8464    9309     372    1318  155000     283    9405   11060     324
##  [19]   10051     742   10496    3834    2004  199000     412    7278   16460
##  [28]    9850   14865   21700   34838     494    4525   12448   17465 1390000
##  [37]   47704     718    4337      21    4805   19840    4307   11271    1129
##  [46]   10660   24763   65705    5598     860      72   10277   15492   80722
##  [55]    6297     736    6131    1291   91729     875    5408   63937    1633
##  [64]    1791    4358   82800   25366   11125     105   15083   11451    1664
##  [73]     795   10174    7936    9976     326 1240000  247000   76424   32778
##  [82]    4576    7644   60885    2769  127000    7009   16271   43178     101
##  [91]    3250    5474    6646    2060    4647    2052    4190    6155    3028
## [100]     524   22294   15906   29240     338   14854     428      53    3796
## [109]    1240  121000     103      38    2796     621   32521   25203   52797
## [118]    2259      10   27474   16714    4460    5992   17157  169000       1
## [127]    4994    3314  179000      21    3802    7167    6687   29988   96707
## [136]   38211   10604    2051   49003    3514   21755  143000   11458      54
## [145]     181     109     189      31     188   28288   13726    9553      92
## [154]    5979    5303    5446    2068     550   10195   52386   10838   46755
## [163]   21098   37195     535    1231    9511    7997   21890    8009   66785
## [172]    2106    1114    6643     105    1337   10875   73997    5173      10
## [181]   36346   45530    9206   62783   47783  318000    3395   28541     247
## [190]   29955   90796   23852   14075   13724
WHO$Population1 <- WHO$Population #dupliramo varijablu population
WHO$Population1 [c(3,8)] <- c(0,1) #na ovaj nacin mijenjamo 3 i 8 observaciju u vektoru istovremeno
#ovdje nemamo zareza jer smo vec odabrali koja je varijabla 
head(WHO$Population1,8) #vidimo da smo zamjenili #8 oznacava prvih 8 redova
## [1] 29825  3162     0    78 20821    89 41087     1
### Izmjena faktora u data.frame-u  
str(WHO) #vidimo da je region factor
## 'data.frame':    194 obs. of  14 variables:
##  $ Country                      : chr  "Afghanistan" "Albania" "Algeria" "Andorra" ...
##  $ Region                       : chr  "Eastern Mediterranean" "Europe" "Africa" "Europe" ...
##  $ Population                   : int  29825 3162 38482 78 20821 89 41087 2969 23050 8464 ...
##  $ Under15                      : num  47.4 21.3 27.4 15.2 47.6 ...
##  $ Over60                       : num  3.82 14.93 7.17 22.86 3.84 ...
##  $ FertilityRate                : num  5.4 1.75 2.83 NA 6.1 2.12 2.2 1.74 1.89 1.44 ...
##  $ LifeExpectancy               : int  60 74 73 82 51 75 76 71 82 81 ...
##  $ ChildMortality               : num  98.5 16.7 20 3.2 163.5 ...
##  $ CellularSubscribers          : num  54.3 96.4 99 75.5 48.4 ...
##  $ LiteracyRate                 : num  NA NA NA NA 70.1 99 97.8 99.6 NA NA ...
##  $ GNI                          : num  1140 8820 8310 NA 5230 ...
##  $ PrimarySchoolEnrollmentMale  : num  NA NA 98.2 78.4 93.1 91.1 NA NA 96.9 NA ...
##  $ PrimarySchoolEnrollmentFemale: num  NA NA 96.4 79.4 78.2 84.5 NA NA 97.5 NA ...
##  $ Population1                  : num  29825 3162 0 78 20821 ...
WHO[6,2] <- "America" #mijenjamo sesti red i drugu kolonu

#prebacimo u character

WHO$Region <- as.character(WHO$Region)
WHO[6,2] <- "America" #sad smo uspijeli
head(WHO$Region)
## [1] "Eastern Mediterranean" "Europe"                "Africa"               
## [4] "Europe"                "Africa"                "America"
#ako zelimo sve Americas mijenjati u America imamo vise nacina ali cemo ih obraditi kasnije. 
#1. ifelse ()
#2. gsub ()


#vratimo varijablu u factor
WHO$Region <- as.factor(WHO$Region)
str(WHO)
## 'data.frame':    194 obs. of  14 variables:
##  $ Country                      : chr  "Afghanistan" "Albania" "Algeria" "Andorra" ...
##  $ Region                       : Factor w/ 7 levels "Africa","America",..: 4 5 1 5 1 2 3 5 7 5 ...
##  $ Population                   : int  29825 3162 38482 78 20821 89 41087 2969 23050 8464 ...
##  $ Under15                      : num  47.4 21.3 27.4 15.2 47.6 ...
##  $ Over60                       : num  3.82 14.93 7.17 22.86 3.84 ...
##  $ FertilityRate                : num  5.4 1.75 2.83 NA 6.1 2.12 2.2 1.74 1.89 1.44 ...
##  $ LifeExpectancy               : int  60 74 73 82 51 75 76 71 82 81 ...
##  $ ChildMortality               : num  98.5 16.7 20 3.2 163.5 ...
##  $ CellularSubscribers          : num  54.3 96.4 99 75.5 48.4 ...
##  $ LiteracyRate                 : num  NA NA NA NA 70.1 99 97.8 99.6 NA NA ...
##  $ GNI                          : num  1140 8820 8310 NA 5230 ...
##  $ PrimarySchoolEnrollmentMale  : num  NA NA 98.2 78.4 93.1 91.1 NA NA 96.9 NA ...
##  $ PrimarySchoolEnrollmentFemale: num  NA NA 96.4 79.4 78.2 84.5 NA NA 97.5 NA ...
##  $ Population1                  : num  29825 3162 0 78 20821 ...
#zadaci ---- 

#izmijenite u WHO$Population1  treci element u broj 10.000
#prije ovakvih stvari savjet je da formirate novu bazu, ali i novu varijablu. Uvijek treba imati tzv master bazu koja je osnovna
#radi toga prvo formirajte WHO1 koja je identicna WHO



##odgovor
WHO1 <- WHO
WHO1$Population1 [3]
## [1] 0
WHO1$Population1 [3] <- 10000
str(WHO1)
## 'data.frame':    194 obs. of  14 variables:
##  $ Country                      : chr  "Afghanistan" "Albania" "Algeria" "Andorra" ...
##  $ Region                       : Factor w/ 7 levels "Africa","America",..: 4 5 1 5 1 2 3 5 7 5 ...
##  $ Population                   : int  29825 3162 38482 78 20821 89 41087 2969 23050 8464 ...
##  $ Under15                      : num  47.4 21.3 27.4 15.2 47.6 ...
##  $ Over60                       : num  3.82 14.93 7.17 22.86 3.84 ...
##  $ FertilityRate                : num  5.4 1.75 2.83 NA 6.1 2.12 2.2 1.74 1.89 1.44 ...
##  $ LifeExpectancy               : int  60 74 73 82 51 75 76 71 82 81 ...
##  $ ChildMortality               : num  98.5 16.7 20 3.2 163.5 ...
##  $ CellularSubscribers          : num  54.3 96.4 99 75.5 48.4 ...
##  $ LiteracyRate                 : num  NA NA NA NA 70.1 99 97.8 99.6 NA NA ...
##  $ GNI                          : num  1140 8820 8310 NA 5230 ...
##  $ PrimarySchoolEnrollmentMale  : num  NA NA 98.2 78.4 93.1 91.1 NA NA 96.9 NA ...
##  $ PrimarySchoolEnrollmentFemale: num  NA NA 96.4 79.4 78.2 84.5 NA NA 97.5 NA ...
##  $ Population1                  : num  29825 3162 10000 78 20821 ...
#dodatno indeksiranje ---- 

which.min(WHO$Population) #dakle indeksira nam red u kojem se nalazi najniza populacija. 
## [1] 126
WHO [126,] # da nam prikaze sve varijable
##     Country          Region Population Under15 Over60 FertilityRate
## 126    Niue Western Pacific          1   30.61   9.07            NA
##     LifeExpectancy ChildMortality CellularSubscribers LiteracyRate GNI
## 126             72           25.1                  NA           NA  NA
##     PrimarySchoolEnrollmentMale PrimarySchoolEnrollmentFemale Population1
## 126                          NA                            NA           1
#zadatak---- 

# po istoj logici koja zemlja ima najvecu Populaciju? 





#odgovor
which.max(WHO$Population)
## [1] 36
WHO[36,] #Kina
##    Country          Region Population Under15 Over60 FertilityRate
## 36   China Western Pacific    1390000   17.95  13.42          1.66
##    LifeExpectancy ChildMortality CellularSubscribers LiteracyRate  GNI
## 36             76             14               73.19         94.3 8390
##    PrimarySchoolEnrollmentMale PrimarySchoolEnrollmentFemale Population1
## 36                          NA                            NA     1390000