how to realize countifs function (excel) in R -


i have dataset containing 100000 rows of data. tried countif operations in excel, prohibitively slow. wondering if kind of operation can done in r? basically, want count based on multiple conditions. example, can count on both occupation , sex

row sex occupation   1   m    student   2   f    analyst   2   m    analyst

easy peasy. data frame this:

df <- data.frame(sex=c('m','f','m'),                  occupation=c('student','analyst','analyst'))

you can equivalent of countif first specifying if part, so:

df$sex == 'm'

this give boolean vector, i.e. vector of true , false. want count observations condition true. since in r true , false double 1 , 0 can sum() on boolean vector. equivalent of countif(sex='m') therefore

sum(df$sex == 'm')

should there rows in sex not specified above give na. in case, if want ignore missing observations use

sum(df$sex == 'm', na.rm=true)

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