nilforooshan

Return the number of decimals

nchar(strsplit(as.character(5.230000), "\\.")[[1]][2])

[1] 2

nchar(strsplit(as.character(5.230200), "\\.")[[1]][2])

nilforooshan

An aggregate example

(data1 <- data.frame(id=c(rep(1,3),rep(2,3)),num=1:6))

  id num
1  1   1
2 1 2

nilforooshan

Inactivate a code block

if(FALSE) {
    print('Hi')
    print('Bye')
}

nilforooshan

Drop/select columns

A sample data:

(df <- data.frame(x=1:5, y=2:6, z=3:7, u=4:8))

 x y z u

nilforooshan

Print unicode character strings

a <- "\U00B5"
cat(a)

µ

nilforooshan

Remove part of strings after occurrence of a character

Remove part of strings after “.”

a <- c("NM_020506.1", "NM_020519.1", "NM_001030297.2", "NM_010281.2", "NM_011419.3", "NM_053155.2")
gsub("\\..*","",a)

[1] "NM_020506" "NM_020519" "NM_001030297" "NM_010281" "NM_011419" "NM_053155"

nilforooshan

match example

A sample data:

(target <- c("b", "c", "a", "d"))
(df <- data.frame(name=letters[1:4], value=c(rep(TRUE, 2), rep(FALSE, 2))))

nilforooshan

List files in a directory and subdirectories

List files matching the pattern in all subdirectories

list.files(pattern = "_input.txt$", recursive = TRUE)

nilforooshan

rm examples

Delete all objects

rm(list=ls())

Delete data

nilforooshan

Count missing values row-wise

A sample data:

(data = data.frame(x=c(NA,NA,3:10), y=11:20, z=c(21,NA,23:30)))

 x y z