how to realize countifs function (excel) in R

Question

I have a dataset containing 100000 rows of data. I tried to do some countif operations in Excel, but it was prohibitively slow. So I am wondering if this kind o

Answer 1

Given a dataset

df <- data.frame( sex = c('M', 'M', 'F', 'F', 'M'), 
                  occupation = c('analyst', 'dentist', 'dentist', 'analyst', 'cook') )

you can subset rows

df[df$sex == 'M',] # To get all males
df[df$occupation == 'analyst',] # All analysts

etc.

If you want to get number of rows, just call the function nrow such as

nrow(df[df$sex == 'M',])