#Load tidyverse
library(tidyverse)
## ── Attaching core tidyverse packages ────── tidyverse 2.0.0 ──
## ✔ dplyr     1.1.4     ✔ readr     2.1.5
## ✔ forcats   1.0.0     ✔ stringr   1.5.1
## ✔ ggplot2   3.5.1     ✔ tibble    3.2.1
## ✔ lubridate 1.9.4     ✔ tidyr     1.3.1
## ✔ purrr     1.0.2     
## ── Conflicts ──────────────────────── tidyverse_conflicts() ──
## ✖ dplyr::filter() masks stats::filter()
## ✖ dplyr::lag()    masks stats::lag()
## ℹ Use the conflicted package (<http://conflicted.r-lib.org/>) to force all conflicts to become errors
#Load the iris dataset
data(iris)

#1. Examine structure of the iris dataset
glimpse(iris)
## Rows: 150
## Columns: 5
## $ Sepal.Length <dbl> 5.1, 4.9, 4.7, 4.6, 5.0, 5.4, 4.6, 5.0, 4.4, 4.9, 5.4, 4.…
## $ Sepal.Width  <dbl> 3.5, 3.0, 3.2, 3.1, 3.6, 3.9, 3.4, 3.4, 2.9, 3.1, 3.7, 3.…
## $ Petal.Length <dbl> 1.4, 1.4, 1.3, 1.5, 1.4, 1.7, 1.4, 1.5, 1.4, 1.5, 1.5, 1.…
## $ Petal.Width  <dbl> 0.2, 0.2, 0.2, 0.2, 0.2, 0.4, 0.3, 0.2, 0.2, 0.1, 0.2, 0.…
## $ Species      <fct> setosa, setosa, setosa, setosa, setosa, setosa, setosa, s…
dim(iris) #Check the number of observations and variables
## [1] 150   5
#2. Create iris 1: filter for species "virginica" and "versicolor with Sepal.Length >6 and Sepal.Widths >2.5
iris1 <- iris%>%
  filter(Species %in% c("virginica", "versicolor"),
    Sepal.Length > 6,
    Sepal.Width > 2.5)
    
dim(iris1) #check dimensions of iris1
## [1] 56  5
#3. Create iris2: select only Species, Sepal.Length, and Sepal. Width
iris2 <- iris1 %>%
  select(Species, Sepal.Length, Sepal.Width)
dim(iris2) #check dimensions of iris2
## [1] 56  3
#4. Create iris3: arrange by Sepal.length in descending order
iris3 <- iris2 %>%
  arrange(desc(Sepal.Length))
head(iris3) #display the first 6 rows
##     Species Sepal.Length Sepal.Width
## 1 virginica          7.9         3.8
## 2 virginica          7.7         3.8
## 3 virginica          7.7         2.6
## 4 virginica          7.7         2.8
## 5 virginica          7.7         3.0
## 6 virginica          7.6         3.0
#5. Create iris4: Add a new colun Sepal.Area (Sepal.Length *Sepal.Width)
iris4 <- iris3 %>%
  mutate(Sepal.Area = Sepal.Length * Sepal.Width)
dim(iris4) #Check dimensions of iris4 
## [1] 56  4
#6. Creae iris5: Summarize to get mean Sepal.Length, mean Sepal. Width, and sample size
iris5 <- iris4 %>%
  summarize(
    Avg_Sepal_Length = mean(Sepal.Length),
    Avg_Sepal_Width = mean(Sepal.Width),
    Sample_Size = n()
  )
print(iris5)
##   Avg_Sepal_Length Avg_Sepal_Width Sample_Size
## 1         6.698214        3.041071          56
#7. Create iris6: Group by species and summarize mean Sepal.Length, meanS epal.Width, and sample size
iris6 <- iris4 %>%
  group_by(Species) %>%
  summarize(
    Avg_Sepal_Length = mean(Sepal.Length),
    Avg_Sepal_Width = mean(Sepal.Width),
    Sample_Size = n()
  )
print(iris6)
## # A tibble: 2 × 4
##   Species    Avg_Sepal_Length Avg_Sepal_Width Sample_Size
##   <fct>                 <dbl>           <dbl>       <int>
## 1 versicolor             6.48            2.99          17
## 2 virginica              6.79            3.06          39
#8. rewrite steps using piping to create irisFinal
irisFinal <- iris %>%
  filter(Species %in% c("virginica", "versicolor"),
         Sepal.Length > 6,
         Sepal.Width > 2.5) %>%
  select(Species, Sepal.Length, Sepal.Width)%>%
  arrange(desc(Sepal.Length)) %>%
  mutate(Septal.Area =Sepal.Length * Sepal.Width)
dim(irisFinal) #Check dimensions of irisFinal
## [1] 56  4
#9. Create a "longer" format data frame with three columns: Species, Measure, and Value

iris_long <- iris %>%
  pivot_longer(cols = c(Sepal.Length, Sepal.Width, Petal.Length, Petal.Width),
               names_to = "Measure",
               values_to = "Value")
head(iris_long) #Display first 6 rows of the longer dataset
## # A tibble: 6 × 3
##   Species Measure      Value
##   <fct>   <chr>        <dbl>
## 1 setosa  Sepal.Length   5.1
## 2 setosa  Sepal.Width    3.5
## 3 setosa  Petal.Length   1.4
## 4 setosa  Petal.Width    0.2
## 5 setosa  Sepal.Length   4.9
## 6 setosa  Sepal.Width    3