options(repos = c(CRAN = "https://cran.rstudio.com"))

install.packages("dplyr")
## package 'dplyr' successfully unpacked and MD5 sums checked
## 
## The downloaded binary packages are in
##  C:\Users\User\AppData\Local\Temp\RtmpsfCzxd\downloaded_packages
install.packages("ggplot2")
## package 'ggplot2' successfully unpacked and MD5 sums checked
## 
## The downloaded binary packages are in
##  C:\Users\User\AppData\Local\Temp\RtmpsfCzxd\downloaded_packages
library(dplyr)
## Warning: package 'dplyr' was built under R version 4.4.2
## 
## 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
library(ggplot2)
## Warning: package 'ggplot2' was built under R version 4.4.2
# Memuat data mtcars
data("mtcars")

# 1. Cek data awal
head(mtcars)
##                    mpg cyl disp  hp drat    wt  qsec vs am gear carb
## Mazda RX4         21.0   6  160 110 3.90 2.620 16.46  0  1    4    4
## Mazda RX4 Wag     21.0   6  160 110 3.90 2.875 17.02  0  1    4    4
## Datsun 710        22.8   4  108  93 3.85 2.320 18.61  1  1    4    1
## Hornet 4 Drive    21.4   6  258 110 3.08 3.215 19.44  1  0    3    1
## Hornet Sportabout 18.7   8  360 175 3.15 3.440 17.02  0  0    3    2
## Valiant           18.1   6  225 105 2.76 3.460 20.22  1  0    3    1
# 2. Meringkas data (Rata-rata mpg dan hp)
ringkasan <- mtcars %>%
  summarise(
    Avg_MPG = mean(mpg),      # Rata-rata miles per gallon
    Avg_HP = mean(hp)         # Rata-rata horsepower
  )
print(ringkasan)
##    Avg_MPG   Avg_HP
## 1 20.09062 146.6875
# 3. Mengurutkan data berdasarkan mpg
data_urut <- mtcars %>%
  arrange(desc(mpg))
head(data_urut)
##                 mpg cyl  disp  hp drat    wt  qsec vs am gear carb
## Toyota Corolla 33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1
## 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
## Lotus Europa   30.4   4  95.1 113 3.77 1.513 16.90  1  1    5    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
# 4. Menyaring data dengan mpg lebih dari 20
data_filter <- mtcars %>%
  filter(mpg > 20)
head(data_filter)
##                 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
## 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
# 5.konversi horsepower ke kilowatt
mtcars_with_kw <- mtcars %>%
  mutate(hp_kw = hp * 0.7457)   
head(mtcars_with_kw)
##                    mpg cyl disp  hp drat    wt  qsec vs am gear carb    hp_kw
## Mazda RX4         21.0   6  160 110 3.90 2.620 16.46  0  1    4    4  82.0270
## Mazda RX4 Wag     21.0   6  160 110 3.90 2.875 17.02  0  1    4    4  82.0270
## Datsun 710        22.8   4  108  93 3.85 2.320 18.61  1  1    4    1  69.3501
## Hornet 4 Drive    21.4   6  258 110 3.08 3.215 19.44  1  0    3    1  82.0270
## Hornet Sportabout 18.7   8  360 175 3.15 3.440 17.02  0  0    3    2 130.4975
## Valiant           18.1   6  225 105 2.76 3.460 20.22  1  0    3    1  78.2985
# 6. Memilih kolom mpg, hp, dan wt
data_terpilih <- mtcars %>%
  select(mpg, hp, wt)
head(data_terpilih)
##                    mpg  hp    wt
## Mazda RX4         21.0 110 2.620
## Mazda RX4 Wag     21.0 110 2.875
## Datsun 710        22.8  93 2.320
## Hornet 4 Drive    21.4 110 3.215
## Hornet Sportabout 18.7 175 3.440
## Valiant           18.1 105 3.460
# 7. mengurutkan berdasarkan mpg
data_combined <- mtcars %>%
  select(mpg, hp, wt) %>%
  filter(mpg > 20) %>%
  arrange(desc(mpg))
head(data_combined)
##                 mpg  hp    wt
## Toyota Corolla 33.9  65 1.835
## Fiat 128       32.4  66 2.200
## Honda Civic    30.4  52 1.615
## Lotus Europa   30.4 113 1.513
## Fiat X1-9      27.3  66 1.935
## Porsche 914-2  26.0  91 2.140
# 8. Membuat scatterplot antara mpg dan hp
plot(mtcars$mpg, mtcars$hp,
     xlab = "Miles per Gallon (mpg)",
     ylab = "Horsepower (hp)",
     main = "Scatterplot MPG vs Horsepower",
     pch = 19, col = "blue")