data(mtcars)
mtcars
##                      mpg cyl  disp  hp drat    wt  qsec vs am gear carb
## Mazda RX4           21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4
## Mazda RX4 Wag       21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4
## Datsun 710          22.8   4 108.0  93 3.85 2.320 18.61  1  1    4    1
## Hornet 4 Drive      21.4   6 258.0 110 3.08 3.215 19.44  1  0    3    1
## Hornet Sportabout   18.7   8 360.0 175 3.15 3.440 17.02  0  0    3    2
## Valiant             18.1   6 225.0 105 2.76 3.460 20.22  1  0    3    1
## Duster 360          14.3   8 360.0 245 3.21 3.570 15.84  0  0    3    4
## Merc 240D           24.4   4 146.7  62 3.69 3.190 20.00  1  0    4    2
## Merc 230            22.8   4 140.8  95 3.92 3.150 22.90  1  0    4    2
## Merc 280            19.2   6 167.6 123 3.92 3.440 18.30  1  0    4    4
## Merc 280C           17.8   6 167.6 123 3.92 3.440 18.90  1  0    4    4
## Merc 450SE          16.4   8 275.8 180 3.07 4.070 17.40  0  0    3    3
## Merc 450SL          17.3   8 275.8 180 3.07 3.730 17.60  0  0    3    3
## Merc 450SLC         15.2   8 275.8 180 3.07 3.780 18.00  0  0    3    3
## Cadillac Fleetwood  10.4   8 472.0 205 2.93 5.250 17.98  0  0    3    4
## Lincoln Continental 10.4   8 460.0 215 3.00 5.424 17.82  0  0    3    4
## Chrysler Imperial   14.7   8 440.0 230 3.23 5.345 17.42  0  0    3    4
## Fiat 128            32.4   4  78.7  66 4.08 2.200 19.47  1  1    4    1
## Honda Civic         30.4   4  75.7  52 4.93 1.615 18.52  1  1    4    2
## Toyota Corolla      33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1
## Toyota Corona       21.5   4 120.1  97 3.70 2.465 20.01  1  0    3    1
## Dodge Challenger    15.5   8 318.0 150 2.76 3.520 16.87  0  0    3    2
## AMC Javelin         15.2   8 304.0 150 3.15 3.435 17.30  0  0    3    2
## Camaro Z28          13.3   8 350.0 245 3.73 3.840 15.41  0  0    3    4
## Pontiac Firebird    19.2   8 400.0 175 3.08 3.845 17.05  0  0    3    2
## Fiat X1-9           27.3   4  79.0  66 4.08 1.935 18.90  1  1    4    1
## Porsche 914-2       26.0   4 120.3  91 4.43 2.140 16.70  0  1    5    2
## Lotus Europa        30.4   4  95.1 113 3.77 1.513 16.90  1  1    5    2
## Ford Pantera L      15.8   8 351.0 264 4.22 3.170 14.50  0  1    5    4
## Ferrari Dino        19.7   6 145.0 175 3.62 2.770 15.50  0  1    5    6
## Maserati Bora       15.0   8 301.0 335 3.54 3.570 14.60  0  1    5    8
## Volvo 142E          21.4   4 121.0 109 4.11 2.780 18.60  1  1    4    2
data(mtcars)
mtcars
##                      mpg cyl  disp  hp drat    wt  qsec vs am gear carb
## Mazda RX4           21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4
## Mazda RX4 Wag       21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4
## Datsun 710          22.8   4 108.0  93 3.85 2.320 18.61  1  1    4    1
## Hornet 4 Drive      21.4   6 258.0 110 3.08 3.215 19.44  1  0    3    1
## Hornet Sportabout   18.7   8 360.0 175 3.15 3.440 17.02  0  0    3    2
## Valiant             18.1   6 225.0 105 2.76 3.460 20.22  1  0    3    1
## Duster 360          14.3   8 360.0 245 3.21 3.570 15.84  0  0    3    4
## Merc 240D           24.4   4 146.7  62 3.69 3.190 20.00  1  0    4    2
## Merc 230            22.8   4 140.8  95 3.92 3.150 22.90  1  0    4    2
## Merc 280            19.2   6 167.6 123 3.92 3.440 18.30  1  0    4    4
## Merc 280C           17.8   6 167.6 123 3.92 3.440 18.90  1  0    4    4
## Merc 450SE          16.4   8 275.8 180 3.07 4.070 17.40  0  0    3    3
## Merc 450SL          17.3   8 275.8 180 3.07 3.730 17.60  0  0    3    3
## Merc 450SLC         15.2   8 275.8 180 3.07 3.780 18.00  0  0    3    3
## Cadillac Fleetwood  10.4   8 472.0 205 2.93 5.250 17.98  0  0    3    4
## Lincoln Continental 10.4   8 460.0 215 3.00 5.424 17.82  0  0    3    4
## Chrysler Imperial   14.7   8 440.0 230 3.23 5.345 17.42  0  0    3    4
## Fiat 128            32.4   4  78.7  66 4.08 2.200 19.47  1  1    4    1
## Honda Civic         30.4   4  75.7  52 4.93 1.615 18.52  1  1    4    2
## Toyota Corolla      33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1
## Toyota Corona       21.5   4 120.1  97 3.70 2.465 20.01  1  0    3    1
## Dodge Challenger    15.5   8 318.0 150 2.76 3.520 16.87  0  0    3    2
## AMC Javelin         15.2   8 304.0 150 3.15 3.435 17.30  0  0    3    2
## Camaro Z28          13.3   8 350.0 245 3.73 3.840 15.41  0  0    3    4
## Pontiac Firebird    19.2   8 400.0 175 3.08 3.845 17.05  0  0    3    2
## Fiat X1-9           27.3   4  79.0  66 4.08 1.935 18.90  1  1    4    1
## Porsche 914-2       26.0   4 120.3  91 4.43 2.140 16.70  0  1    5    2
## Lotus Europa        30.4   4  95.1 113 3.77 1.513 16.90  1  1    5    2
## Ford Pantera L      15.8   8 351.0 264 4.22 3.170 14.50  0  1    5    4
## Ferrari Dino        19.7   6 145.0 175 3.62 2.770 15.50  0  1    5    6
## Maserati Bora       15.0   8 301.0 335 3.54 3.570 14.60  0  1    5    8
## Volvo 142E          21.4   4 121.0 109 4.11 2.780 18.60  1  1    4    2
library(dplyr)
## Warning: package 'dplyr' was built under R version 4.4.3
## 
## Attaching package: 'dplyr'
## The following objects are masked from 'package:stats':
## 
##     filter, lag
## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union
glimpse(mtcars)
## Rows: 32
## Columns: 11
## $ mpg  <dbl> 21.0, 21.0, 22.8, 21.4, 18.7, 18.1, 14.3, 24.4, 22.8, 19.2, 17.8,…
## $ cyl  <dbl> 6, 6, 4, 6, 8, 6, 8, 4, 4, 6, 6, 8, 8, 8, 8, 8, 8, 4, 4, 4, 4, 8,…
## $ disp <dbl> 160.0, 160.0, 108.0, 258.0, 360.0, 225.0, 360.0, 146.7, 140.8, 16…
## $ hp   <dbl> 110, 110, 93, 110, 175, 105, 245, 62, 95, 123, 123, 180, 180, 180…
## $ drat <dbl> 3.90, 3.90, 3.85, 3.08, 3.15, 2.76, 3.21, 3.69, 3.92, 3.92, 3.92,…
## $ wt   <dbl> 2.620, 2.875, 2.320, 3.215, 3.440, 3.460, 3.570, 3.190, 3.150, 3.…
## $ qsec <dbl> 16.46, 17.02, 18.61, 19.44, 17.02, 20.22, 15.84, 20.00, 22.90, 18…
## $ vs   <dbl> 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0,…
## $ am   <dbl> 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0,…
## $ gear <dbl> 4, 4, 4, 3, 3, 3, 3, 4, 4, 4, 4, 3, 3, 3, 3, 3, 3, 4, 4, 4, 3, 3,…
## $ carb <dbl> 4, 4, 1, 1, 2, 1, 4, 2, 2, 4, 4, 3, 3, 3, 4, 4, 4, 1, 2, 1, 1, 2,…
mtcars2 <- within(mtcars, {
  vs <- factor(vs, labels = c("V", "S"))
  am <- factor(am, labels = c("automatic", "manual"))
  cyl <- ordered(cyl)
  gear <- ordered(gear)
  carb <- ordered(carb)
})
glimpse(mtcars2)
## Rows: 32
## Columns: 11
## $ mpg  <dbl> 21.0, 21.0, 22.8, 21.4, 18.7, 18.1, 14.3, 24.4, 22.8, 19.2, 17.8,…
## $ cyl  <ord> 6, 6, 4, 6, 8, 6, 8, 4, 4, 6, 6, 8, 8, 8, 8, 8, 8, 4, 4, 4, 4, 8,…
## $ disp <dbl> 160.0, 160.0, 108.0, 258.0, 360.0, 225.0, 360.0, 146.7, 140.8, 16…
## $ hp   <dbl> 110, 110, 93, 110, 175, 105, 245, 62, 95, 123, 123, 180, 180, 180…
## $ drat <dbl> 3.90, 3.90, 3.85, 3.08, 3.15, 2.76, 3.21, 3.69, 3.92, 3.92, 3.92,…
## $ wt   <dbl> 2.620, 2.875, 2.320, 3.215, 3.440, 3.460, 3.570, 3.190, 3.150, 3.…
## $ qsec <dbl> 16.46, 17.02, 18.61, 19.44, 17.02, 20.22, 15.84, 20.00, 22.90, 18…
## $ vs   <fct> V, V, S, S, V, S, V, S, S, S, S, V, V, V, V, V, V, S, S, S, S, V,…
## $ am   <fct> manual, manual, manual, automatic, automatic, automatic, automati…
## $ gear <ord> 4, 4, 4, 3, 3, 3, 3, 4, 4, 4, 4, 3, 3, 3, 3, 3, 3, 4, 4, 4, 3, 3,…
## $ carb <ord> 4, 4, 1, 1, 2, 1, 4, 2, 2, 4, 4, 3, 3, 3, 4, 4, 4, 1, 2, 1, 1, 2,…
summary(mtcars2)
##       mpg        cyl         disp             hp             drat      
##  Min.   :10.40   4:11   Min.   : 71.1   Min.   : 52.0   Min.   :2.760  
##  1st Qu.:15.43   6: 7   1st Qu.:120.8   1st Qu.: 96.5   1st Qu.:3.080  
##  Median :19.20   8:14   Median :196.3   Median :123.0   Median :3.695  
##  Mean   :20.09          Mean   :230.7   Mean   :146.7   Mean   :3.597  
##  3rd Qu.:22.80          3rd Qu.:326.0   3rd Qu.:180.0   3rd Qu.:3.920  
##  Max.   :33.90          Max.   :472.0   Max.   :335.0   Max.   :4.930  
##        wt             qsec       vs             am     gear   carb  
##  Min.   :1.513   Min.   :14.50   V:18   automatic:19   3:15   1: 7  
##  1st Qu.:2.581   1st Qu.:16.89   S:14   manual   :13   4:12   2:10  
##  Median :3.325   Median :17.71                         5: 5   3: 3  
##  Mean   :3.217   Mean   :17.85                                4:10  
##  3rd Qu.:3.610   3rd Qu.:18.90                                6: 1  
##  Max.   :5.424   Max.   :22.90                                8: 1
mtcars2 %>%
  filter(cyl == 4)
##                 mpg cyl  disp  hp drat    wt  qsec vs        am gear carb
## Datsun 710     22.8   4 108.0  93 3.85 2.320 18.61  S    manual    4    1
## Merc 240D      24.4   4 146.7  62 3.69 3.190 20.00  S automatic    4    2
## Merc 230       22.8   4 140.8  95 3.92 3.150 22.90  S automatic    4    2
## Fiat 128       32.4   4  78.7  66 4.08 2.200 19.47  S    manual    4    1
## Honda Civic    30.4   4  75.7  52 4.93 1.615 18.52  S    manual    4    2
## Toyota Corolla 33.9   4  71.1  65 4.22 1.835 19.90  S    manual    4    1
## Toyota Corona  21.5   4 120.1  97 3.70 2.465 20.01  S automatic    3    1
## Fiat X1-9      27.3   4  79.0  66 4.08 1.935 18.90  S    manual    4    1
## Porsche 914-2  26.0   4 120.3  91 4.43 2.140 16.70  V    manual    5    2
## Lotus Europa   30.4   4  95.1 113 3.77 1.513 16.90  S    manual    5    2
## Volvo 142E     21.4   4 121.0 109 4.11 2.780 18.60  S    manual    4    2
mtcars2 %>%
  filter(cyl == 4) %>%
  arrange(wt) %>%
  head()
##                 mpg cyl  disp  hp drat    wt  qsec vs     am gear carb
## Lotus Europa   30.4   4  95.1 113 3.77 1.513 16.90  S manual    5    2
## Honda Civic    30.4   4  75.7  52 4.93 1.615 18.52  S manual    4    2
## Toyota Corolla 33.9   4  71.1  65 4.22 1.835 19.90  S manual    4    1
## Fiat X1-9      27.3   4  79.0  66 4.08 1.935 18.90  S manual    4    1
## Porsche 914-2  26.0   4 120.3  91 4.43 2.140 16.70  V manual    5    2
## Fiat 128       32.4   4  78.7  66 4.08 2.200 19.47  S manual    4    1
mtcars2 %>%
  filter(cyl == 4) %>%
  arrange(desc(wt)) %>%
  head()
##                mpg cyl  disp  hp drat    wt  qsec vs        am gear carb
## Merc 240D     24.4   4 146.7  62 3.69 3.190 20.00  S automatic    4    2
## Merc 230      22.8   4 140.8  95 3.92 3.150 22.90  S automatic    4    2
## Volvo 142E    21.4   4 121.0 109 4.11 2.780 18.60  S    manual    4    2
## Toyota Corona 21.5   4 120.1  97 3.70 2.465 20.01  S automatic    3    1
## Datsun 710    22.8   4 108.0  93 3.85 2.320 18.61  S    manual    4    1
## Fiat 128      32.4   4  78.7  66 4.08 2.200 19.47  S    manual    4    1
mtcars2 %>%
  filter(mpg > 20) %>%
  arrange(hp) %>%
  head()
##                 mpg cyl  disp hp drat    wt  qsec vs        am gear carb
## Honda Civic    30.4   4  75.7 52 4.93 1.615 18.52  S    manual    4    2
## Merc 240D      24.4   4 146.7 62 3.69 3.190 20.00  S automatic    4    2
## Toyota Corolla 33.9   4  71.1 65 4.22 1.835 19.90  S    manual    4    1
## Fiat 128       32.4   4  78.7 66 4.08 2.200 19.47  S    manual    4    1
## Fiat X1-9      27.3   4  79.0 66 4.08 1.935 18.90  S    manual    4    1
## Porsche 914-2  26.0   4 120.3 91 4.43 2.140 16.70  V    manual    5    2
mtcars2 %>%
  filter(between(mpg, 15, 25))
##                    mpg cyl  disp  hp drat    wt  qsec vs        am gear carb
## Mazda RX4         21.0   6 160.0 110 3.90 2.620 16.46  V    manual    4    4
## Mazda RX4 Wag     21.0   6 160.0 110 3.90 2.875 17.02  V    manual    4    4
## Datsun 710        22.8   4 108.0  93 3.85 2.320 18.61  S    manual    4    1
## Hornet 4 Drive    21.4   6 258.0 110 3.08 3.215 19.44  S automatic    3    1
## Hornet Sportabout 18.7   8 360.0 175 3.15 3.440 17.02  V automatic    3    2
## Valiant           18.1   6 225.0 105 2.76 3.460 20.22  S automatic    3    1
## Merc 240D         24.4   4 146.7  62 3.69 3.190 20.00  S automatic    4    2
## Merc 230          22.8   4 140.8  95 3.92 3.150 22.90  S automatic    4    2
## Merc 280          19.2   6 167.6 123 3.92 3.440 18.30  S automatic    4    4
## Merc 280C         17.8   6 167.6 123 3.92 3.440 18.90  S automatic    4    4
## Merc 450SE        16.4   8 275.8 180 3.07 4.070 17.40  V automatic    3    3
## Merc 450SL        17.3   8 275.8 180 3.07 3.730 17.60  V automatic    3    3
## Merc 450SLC       15.2   8 275.8 180 3.07 3.780 18.00  V automatic    3    3
## Toyota Corona     21.5   4 120.1  97 3.70 2.465 20.01  S automatic    3    1
## Dodge Challenger  15.5   8 318.0 150 2.76 3.520 16.87  V automatic    3    2
## AMC Javelin       15.2   8 304.0 150 3.15 3.435 17.30  V automatic    3    2
## Pontiac Firebird  19.2   8 400.0 175 3.08 3.845 17.05  V automatic    3    2
## Ford Pantera L    15.8   8 351.0 264 4.22 3.170 14.50  V    manual    5    4
## Ferrari Dino      19.7   6 145.0 175 3.62 2.770 15.50  V    manual    5    6
## Maserati Bora     15.0   8 301.0 335 3.54 3.570 14.60  V    manual    5    8
## Volvo 142E        21.4   4 121.0 109 4.11 2.780 18.60  S    manual    4    2
mtcars2 %>%
  filter(between(mpg, 2, 3.3))
##  [1] mpg  cyl  disp hp   drat wt   qsec vs   am   gear carb
## <0 rows> (or 0-length row.names)
mtcars2%>%
  select(where(is.character))
## data frame with 0 columns and 32 rows
mtcars2%>%
  select(where(is.character))
## data frame with 0 columns and 32 rows
mtcars2%>%
  select(where(is.numeric))
##                      mpg  disp  hp drat    wt  qsec
## Mazda RX4           21.0 160.0 110 3.90 2.620 16.46
## Mazda RX4 Wag       21.0 160.0 110 3.90 2.875 17.02
## Datsun 710          22.8 108.0  93 3.85 2.320 18.61
## Hornet 4 Drive      21.4 258.0 110 3.08 3.215 19.44
## Hornet Sportabout   18.7 360.0 175 3.15 3.440 17.02
## Valiant             18.1 225.0 105 2.76 3.460 20.22
## Duster 360          14.3 360.0 245 3.21 3.570 15.84
## Merc 240D           24.4 146.7  62 3.69 3.190 20.00
## Merc 230            22.8 140.8  95 3.92 3.150 22.90
## Merc 280            19.2 167.6 123 3.92 3.440 18.30
## Merc 280C           17.8 167.6 123 3.92 3.440 18.90
## Merc 450SE          16.4 275.8 180 3.07 4.070 17.40
## Merc 450SL          17.3 275.8 180 3.07 3.730 17.60
## Merc 450SLC         15.2 275.8 180 3.07 3.780 18.00
## Cadillac Fleetwood  10.4 472.0 205 2.93 5.250 17.98
## Lincoln Continental 10.4 460.0 215 3.00 5.424 17.82
## Chrysler Imperial   14.7 440.0 230 3.23 5.345 17.42
## Fiat 128            32.4  78.7  66 4.08 2.200 19.47
## Honda Civic         30.4  75.7  52 4.93 1.615 18.52
## Toyota Corolla      33.9  71.1  65 4.22 1.835 19.90
## Toyota Corona       21.5 120.1  97 3.70 2.465 20.01
## Dodge Challenger    15.5 318.0 150 2.76 3.520 16.87
## AMC Javelin         15.2 304.0 150 3.15 3.435 17.30
## Camaro Z28          13.3 350.0 245 3.73 3.840 15.41
## Pontiac Firebird    19.2 400.0 175 3.08 3.845 17.05
## Fiat X1-9           27.3  79.0  66 4.08 1.935 18.90
## Porsche 914-2       26.0 120.3  91 4.43 2.140 16.70
## Lotus Europa        30.4  95.1 113 3.77 1.513 16.90
## Ford Pantera L      15.8 351.0 264 4.22 3.170 14.50
## Ferrari Dino        19.7 145.0 175 3.62 2.770 15.50
## Maserati Bora       15.0 301.0 335 3.54 3.570 14.60
## Volvo 142E          21.4 121.0 109 4.11 2.780 18.60
mtcars2 %>%
  mutate(weight_kg = wt * 1000 * 0.45359237)
##                      mpg cyl  disp  hp drat    wt  qsec vs        am gear carb
## Mazda RX4           21.0   6 160.0 110 3.90 2.620 16.46  V    manual    4    4
## Mazda RX4 Wag       21.0   6 160.0 110 3.90 2.875 17.02  V    manual    4    4
## Datsun 710          22.8   4 108.0  93 3.85 2.320 18.61  S    manual    4    1
## Hornet 4 Drive      21.4   6 258.0 110 3.08 3.215 19.44  S automatic    3    1
## Hornet Sportabout   18.7   8 360.0 175 3.15 3.440 17.02  V automatic    3    2
## Valiant             18.1   6 225.0 105 2.76 3.460 20.22  S automatic    3    1
## Duster 360          14.3   8 360.0 245 3.21 3.570 15.84  V automatic    3    4
## Merc 240D           24.4   4 146.7  62 3.69 3.190 20.00  S automatic    4    2
## Merc 230            22.8   4 140.8  95 3.92 3.150 22.90  S automatic    4    2
## Merc 280            19.2   6 167.6 123 3.92 3.440 18.30  S automatic    4    4
## Merc 280C           17.8   6 167.6 123 3.92 3.440 18.90  S automatic    4    4
## Merc 450SE          16.4   8 275.8 180 3.07 4.070 17.40  V automatic    3    3
## Merc 450SL          17.3   8 275.8 180 3.07 3.730 17.60  V automatic    3    3
## Merc 450SLC         15.2   8 275.8 180 3.07 3.780 18.00  V automatic    3    3
## Cadillac Fleetwood  10.4   8 472.0 205 2.93 5.250 17.98  V automatic    3    4
## Lincoln Continental 10.4   8 460.0 215 3.00 5.424 17.82  V automatic    3    4
## Chrysler Imperial   14.7   8 440.0 230 3.23 5.345 17.42  V automatic    3    4
## Fiat 128            32.4   4  78.7  66 4.08 2.200 19.47  S    manual    4    1
## Honda Civic         30.4   4  75.7  52 4.93 1.615 18.52  S    manual    4    2
## Toyota Corolla      33.9   4  71.1  65 4.22 1.835 19.90  S    manual    4    1
## Toyota Corona       21.5   4 120.1  97 3.70 2.465 20.01  S automatic    3    1
## Dodge Challenger    15.5   8 318.0 150 2.76 3.520 16.87  V automatic    3    2
## AMC Javelin         15.2   8 304.0 150 3.15 3.435 17.30  V automatic    3    2
## Camaro Z28          13.3   8 350.0 245 3.73 3.840 15.41  V automatic    3    4
## Pontiac Firebird    19.2   8 400.0 175 3.08 3.845 17.05  V automatic    3    2
## Fiat X1-9           27.3   4  79.0  66 4.08 1.935 18.90  S    manual    4    1
## Porsche 914-2       26.0   4 120.3  91 4.43 2.140 16.70  V    manual    5    2
## Lotus Europa        30.4   4  95.1 113 3.77 1.513 16.90  S    manual    5    2
## Ford Pantera L      15.8   8 351.0 264 4.22 3.170 14.50  V    manual    5    4
## Ferrari Dino        19.7   6 145.0 175 3.62 2.770 15.50  V    manual    5    6
## Maserati Bora       15.0   8 301.0 335 3.54 3.570 14.60  V    manual    5    8
## Volvo 142E          21.4   4 121.0 109 4.11 2.780 18.60  S    manual    4    2
##                     weight_kg
## Mazda RX4           1188.4120
## Mazda RX4 Wag       1304.0781
## Datsun 710          1052.3343
## Hornet 4 Drive      1458.2995
## Hornet Sportabout   1560.3578
## Valiant             1569.4296
## Duster 360          1619.3248
## Merc 240D           1446.9597
## Merc 230            1428.8160
## Merc 280            1560.3578
## Merc 280C           1560.3578
## Merc 450SE          1846.1209
## Merc 450SL          1691.8995
## Merc 450SLC         1714.5792
## Cadillac Fleetwood  2381.3599
## Lincoln Continental 2460.2850
## Chrysler Imperial   2424.4512
## Fiat 128             997.9032
## Honda Civic          732.5517
## Toyota Corolla       832.3420
## Toyota Corona       1118.1052
## Dodge Challenger    1596.6451
## AMC Javelin         1558.0898
## Camaro Z28          1741.7947
## Pontiac Firebird    1744.0627
## Fiat X1-9            877.7012
## Porsche 914-2        970.6877
## Lotus Europa         686.2853
## Ford Pantera L      1437.8878
## Ferrari Dino        1256.4509
## Maserati Bora       1619.3248
## Volvo 142E          1260.9868
mtcars2 %>%
  mutate(weight_kg = wt * 1000 * 0.45359237) %>%
  select(everything())
##                      mpg cyl  disp  hp drat    wt  qsec vs        am gear carb
## Mazda RX4           21.0   6 160.0 110 3.90 2.620 16.46  V    manual    4    4
## Mazda RX4 Wag       21.0   6 160.0 110 3.90 2.875 17.02  V    manual    4    4
## Datsun 710          22.8   4 108.0  93 3.85 2.320 18.61  S    manual    4    1
## Hornet 4 Drive      21.4   6 258.0 110 3.08 3.215 19.44  S automatic    3    1
## Hornet Sportabout   18.7   8 360.0 175 3.15 3.440 17.02  V automatic    3    2
## Valiant             18.1   6 225.0 105 2.76 3.460 20.22  S automatic    3    1
## Duster 360          14.3   8 360.0 245 3.21 3.570 15.84  V automatic    3    4
## Merc 240D           24.4   4 146.7  62 3.69 3.190 20.00  S automatic    4    2
## Merc 230            22.8   4 140.8  95 3.92 3.150 22.90  S automatic    4    2
## Merc 280            19.2   6 167.6 123 3.92 3.440 18.30  S automatic    4    4
## Merc 280C           17.8   6 167.6 123 3.92 3.440 18.90  S automatic    4    4
## Merc 450SE          16.4   8 275.8 180 3.07 4.070 17.40  V automatic    3    3
## Merc 450SL          17.3   8 275.8 180 3.07 3.730 17.60  V automatic    3    3
## Merc 450SLC         15.2   8 275.8 180 3.07 3.780 18.00  V automatic    3    3
## Cadillac Fleetwood  10.4   8 472.0 205 2.93 5.250 17.98  V automatic    3    4
## Lincoln Continental 10.4   8 460.0 215 3.00 5.424 17.82  V automatic    3    4
## Chrysler Imperial   14.7   8 440.0 230 3.23 5.345 17.42  V automatic    3    4
## Fiat 128            32.4   4  78.7  66 4.08 2.200 19.47  S    manual    4    1
## Honda Civic         30.4   4  75.7  52 4.93 1.615 18.52  S    manual    4    2
## Toyota Corolla      33.9   4  71.1  65 4.22 1.835 19.90  S    manual    4    1
## Toyota Corona       21.5   4 120.1  97 3.70 2.465 20.01  S automatic    3    1
## Dodge Challenger    15.5   8 318.0 150 2.76 3.520 16.87  V automatic    3    2
## AMC Javelin         15.2   8 304.0 150 3.15 3.435 17.30  V automatic    3    2
## Camaro Z28          13.3   8 350.0 245 3.73 3.840 15.41  V automatic    3    4
## Pontiac Firebird    19.2   8 400.0 175 3.08 3.845 17.05  V automatic    3    2
## Fiat X1-9           27.3   4  79.0  66 4.08 1.935 18.90  S    manual    4    1
## Porsche 914-2       26.0   4 120.3  91 4.43 2.140 16.70  V    manual    5    2
## Lotus Europa        30.4   4  95.1 113 3.77 1.513 16.90  S    manual    5    2
## Ford Pantera L      15.8   8 351.0 264 4.22 3.170 14.50  V    manual    5    4
## Ferrari Dino        19.7   6 145.0 175 3.62 2.770 15.50  V    manual    5    6
## Maserati Bora       15.0   8 301.0 335 3.54 3.570 14.60  V    manual    5    8
## Volvo 142E          21.4   4 121.0 109 4.11 2.780 18.60  S    manual    4    2
##                     weight_kg
## Mazda RX4           1188.4120
## Mazda RX4 Wag       1304.0781
## Datsun 710          1052.3343
## Hornet 4 Drive      1458.2995
## Hornet Sportabout   1560.3578
## Valiant             1569.4296
## Duster 360          1619.3248
## Merc 240D           1446.9597
## Merc 230            1428.8160
## Merc 280            1560.3578
## Merc 280C           1560.3578
## Merc 450SE          1846.1209
## Merc 450SL          1691.8995
## Merc 450SLC         1714.5792
## Cadillac Fleetwood  2381.3599
## Lincoln Continental 2460.2850
## Chrysler Imperial   2424.4512
## Fiat 128             997.9032
## Honda Civic          732.5517
## Toyota Corolla       832.3420
## Toyota Corona       1118.1052
## Dodge Challenger    1596.6451
## AMC Javelin         1558.0898
## Camaro Z28          1741.7947
## Pontiac Firebird    1744.0627
## Fiat X1-9            877.7012
## Porsche 914-2        970.6877
## Lotus Europa         686.2853
## Ford Pantera L      1437.8878
## Ferrari Dino        1256.4509
## Maserati Bora       1619.3248
## Volvo 142E          1260.9868
mtcars2 %>%
  summarise(avg_weight = mean(wt))
##   avg_weight
## 1    3.21725
mtcars2 %>%
  summarise(avg_weight = mean(wt, na.rm = TRUE))
##   avg_weight
## 1    3.21725
mtcars2 %>%
  group_by(cyl) %>%
  summarise(avg_weight = mean(wt))
## # A tibble: 3 × 2
##   cyl   avg_weight
##   <ord>      <dbl>
## 1 4           2.29
## 2 6           3.12
## 3 8           4.00
library(ggplot2)
## Warning: package 'ggplot2' was built under R version 4.4.3
ggplot(data = mtcars, aes(x = wt, y = mpg)) +
  geom_point()

ggplot(data = mtcars, aes(x = wt, y = mpg)) +
  geom_point() +
  labs(
    title = "Hubungan Berat Mobil dan Efisiensi Bahan Bakar",
    x = "Berat (1000 lbs)",
    y = "Miles per Gallon"
  )

ggplot(data = mtcars, aes(x = wt, y = mpg, color = factor(cyl))) +
  geom_point() +
  labs(
    title = "Hubungan Berat Mobil dan Efisiensi Bahan Bakar berdasarkan Silinder",
    x = "Berat (1000 lbs)",
    y = "Miles per Gallon",
    color ="Jumlah Silinder"
  )

ggplot(data = mtcars, aes(x = wt, y = mpg, color= factor(cyl))) +
  geom_point() +
  geom_smooth(method = "lm", se = FALSE, color = "pink") +
  labs(
    title = "Berat vs Efisiensi Bahan Bakar dengan Garis Regresi",
    x = "Berat (1000 lbs)",
    y = "Miles per Gallon"
  )
## `geom_smooth()` using formula = 'y ~ x'

mtcars_summary <- mtcars %>%
  group_by(cyl) %>%
  summarise(count = n())

ggplot(data = mtcars_summary, aes(x = factor(cyl), y = count)) +
  geom_bar(stat = "identity", fill = "deeppink") +
  labs(
    title = "Distribusi Mobil Berdasarkan Jumlah Silinder",
    x = "Jumlah Silinder",
    y = "Jumlah Mobil"
  )

ggplot(data = mtcars, aes(x = wt, y = mpg)) +
  geom_point() +
  facet_wrap(~ cyl)+
  labs(
    title = "Berat vs Efisiensi Bahan Bakar dengan Garis Regresi",
    x = "Berat (1000 lbs)",
    y = "Miles per Gallon"
  )

ggplot(data = mtcars, aes(x = wt, y = mpg)) +
  geom_point() +
  labs(title = "Scatter Plot Berat vs MPG")