Import Library

library(plyr)
library(dplyr)
## 
## Attaching package: 'dplyr'
## The following objects are masked from 'package:plyr':
## 
##     arrange, count, desc, failwith, id, mutate, rename, summarise,
##     summarize
## The following objects are masked from 'package:stats':
## 
##     filter, lag
## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union

Read The file Using read_csv function

mtcars_Data <- read.csv("C:\\Users\\HP\\Documents\\R\\Project_2\\Rscripts\\mtcars.csv")

view the top rows

head(mtcars_Data)
##               model  mpg cyl disp  hp drat    wt  qsec vs am gear carb
## 1         Mazda RX4 21.0   6  160 110 3.90 2.620 16.46  0  1    4    4
## 2     Mazda RX4 Wag 21.0   6  160 110 3.90 2.875 17.02  0  1    4    4
## 3        Datsun 710 22.8   4  108  93 3.85 2.320 18.61  1  1    4    1
## 4    Hornet 4 Drive 21.4   6  258 110 3.08 3.215 19.44  1  0    3    1
## 5 Hornet Sportabout 18.7   8  360 175 3.15 3.440 17.02  0  0    3    2
## 6           Valiant 18.1   6  225 105 2.76 3.460 20.22  1  0    3    1
attach(mtcars_Data)# For Without Giving $ sign to accessing the columns

Question and Answer Regarding this dataset

1. get the unique count of cars?

mtcars_Data %>%  
  summarise(unique_count_cars = n_distinct(model))
##   unique_count_cars
## 1                32

Insight: Their are 32 no of unique car in the dataset

2. get mean of weight by cylinder?

mtcars_Data %>% group_by(cyl) %>% 
  summarise(mean_of_weight = mean(wt))
## `summarise()` ungrouping output (override with `.groups` argument)
## # A tibble: 3 x 2
##     cyl mean_of_weight
##   <int>          <dbl>
## 1     4           2.29
## 2     6           3.12
## 3     8           4.00

Insight: The above table denotes the reasult

3. get the no of cars by gear?

mtcars_Data %>% group_by(gear) %>% 
  summarise(Count_Of_Cars = n_distinct(model))
## `summarise()` ungrouping output (override with `.groups` argument)
## # A tibble: 3 x 2
##    gear Count_Of_Cars
##   <int>         <int>
## 1     3            15
## 2     4            12
## 3     5             5

Insight: The above table denotes the reasult

4. get mean mpg by gear and carb and cyl?

mtcars_Data %>% group_by(gear) %>% 
  summarise(mean_mpg_by_gear = mean(mpg))
## `summarise()` ungrouping output (override with `.groups` argument)
## # A tibble: 3 x 2
##    gear mean_mpg_by_gear
##   <int>            <dbl>
## 1     3             16.1
## 2     4             24.5
## 3     5             21.4

Insight: The above table denotes the reasult ‘mean_mpg_by_gear’

mtcars_Data %>% group_by(cyl) %>% 
  summarise(mean_carb_by_cyl = mean(carb))
## `summarise()` ungrouping output (override with `.groups` argument)
## # A tibble: 3 x 2
##     cyl mean_carb_by_cyl
##   <int>            <dbl>
## 1     4             1.55
## 2     6             3.43
## 3     8             3.5

Insight: The above table denotes the reasult’mean_carb_by_cyl’

5. which car has the max hp ?

mtcars_Data %>% 
filter(hp == max(hp)) %>%
select(model, hp)
##           model  hp
## 1 Maserati Bora 335

Insight: Maserati Bora has Highest HP-‘335’

6. which car has the minimum displacement ?

mtcars_Data %>% 
filter(disp == min(disp)) %>%
select(model, disp)
##            model disp
## 1 Toyota Corolla 71.1

Insight: Toyota Corolla has MIN DISP-‘71.1’

7. get summary of the data?

summary(mtcars_Data)
##     model                mpg             cyl             disp      
##  Length:32          Min.   :10.40   Min.   :4.000   Min.   : 71.1  
##  Class :character   1st Qu.:15.43   1st Qu.:4.000   1st Qu.:120.8  
##  Mode  :character   Median :19.20   Median :6.000   Median :196.3  
##                     Mean   :20.09   Mean   :6.188   Mean   :230.7  
##                     3rd Qu.:22.80   3rd Qu.:8.000   3rd Qu.:326.0  
##                     Max.   :33.90   Max.   :8.000   Max.   :472.0  
##        hp             drat             wt             qsec      
##  Min.   : 52.0   Min.   :2.760   Min.   :1.513   Min.   :14.50  
##  1st Qu.: 96.5   1st Qu.:3.080   1st Qu.:2.581   1st Qu.:16.89  
##  Median :123.0   Median :3.695   Median :3.325   Median :17.71  
##  Mean   :146.7   Mean   :3.597   Mean   :3.217   Mean   :17.85  
##  3rd Qu.:180.0   3rd Qu.:3.920   3rd Qu.:3.610   3rd Qu.:18.90  
##  Max.   :335.0   Max.   :4.930   Max.   :5.424   Max.   :22.90  
##        vs               am              gear            carb      
##  Min.   :0.0000   Min.   :0.0000   Min.   :3.000   Min.   :1.000  
##  1st Qu.:0.0000   1st Qu.:0.0000   1st Qu.:3.000   1st Qu.:2.000  
##  Median :0.0000   Median :0.0000   Median :4.000   Median :2.000  
##  Mean   :0.4375   Mean   :0.4062   Mean   :3.688   Mean   :2.812  
##  3rd Qu.:1.0000   3rd Qu.:1.0000   3rd Qu.:4.000   3rd Qu.:4.000  
##  Max.   :1.0000   Max.   :1.0000   Max.   :5.000   Max.   :8.000

9. out of all the cars with 4 cyl which car has max displ and min hp?

mtcars_Data %>% 
filter((cyl==4))%>%
select(model,cyl,hp, disp)->mycars_data_processed # First i subset the data with given condition

mycars_data_processed %>% 
filter((disp==max(disp)))%>%
select(model,cyl, disp) # Final processed the data
##       model cyl  disp
## 1 Merc 240D   4 146.7

Insight: Merc 240D has max disp among all 4 cyl car.

mycars_data_processed %>% 
filter((hp==min(hp)))%>%
select(model,cyl,hp)
##         model cyl hp
## 1 Honda Civic   4 52

Insight: Honda Civic has min hp among all 4 cyl car.

10. out of all the cars with 4 gear and >=4 cyl which car has max displ and min hp?

mtcars_Data %>% 
filter((gear==4)& (cyl>=4))%>%
select(model,gear,cyl,hp, disp)->mycars_data_processed_2
mycars_data_processed_2 %>% 
filter((disp==max(disp)))%>%
select(model,gear,cyl, disp)
##       model gear cyl  disp
## 1  Merc 280    4   6 167.6
## 2 Merc 280C    4   6 167.6

Insight: Merc 280 and Merc 280C has max disp among all the cars with 4 gear and >=4 cyl

mycars_data_processed_2 %>% 
filter((hp==min(hp)))%>%
select(model,gear,cyl, hp)
##         model gear cyl hp
## 1 Honda Civic    4   4 52

Insight: Honda Civic has min hp among all the cars with 4 gear and >=4 cyl

detach(mtcars_Data)