Working with dataframes

Reading dataframe

df <- read.csv("https://goo.gl/v7nvho")

Getting first rows

head(df)

Accessing column

df$Age

Finding descriptive statistics

mean(df$Age)
max(df$Age)
min(df$Age)

Factor (categorical) variable

df$Gender

Accessing rows

df[1,]

df[2,]

df[2]

Accessing items

df[3,7]

Accessing columns (different way)

df[,1]

df[,'Age']

Accessing severals rows

df[1:4,]

df[2:4,]

df[c(1, 3, 2, 5),]

Plotting histograms

hist(df$Age)

Selecting number of bins

hist(df$Age, 20)

hist(df$Age, 40)

hist(df$Age, 100000)

Some simulations. Generating normally distributed random numbers

x <- rnorm(1000)

Plotting histograms with different number of bins

hist(x)

hist(x, 500)

hist(x, 2000)

hist(x, 20000)

hist(x, col='blue')

If you need help, you can use

?hist