columns: Column Actions

Description

Perform actions on columns.

Usage

columns(
  data,
  col1 = NA,
  col2 = NA,
  operator = "&",
  fixed = NA,
  target = NA,
  start = 1,
  stop = 1,
  debug = FALSE
)

Value

data frame.

Arguments

data: a data frame.
col1: character column name to perform action on.
col2: character optional second column name to perform action on.
operator: character to indicate operator: '&' concatenate, '+' add, '*' multiply, '-' subtract, '/' divide, 'substr' extract a substring.
fixed: character or numeric providing the second operand if 'col2' is not used.
target: character to specify column name for result. Default is to overwrite 'col1'. If not present it will be added.
start: integer, the first position to be extracted.
stop: integer, the last position to be extracted.
debug: logical to indicate if debug information should be printed.

Details

Perform actions on columns in a data frame. There are five actions: concatenate, add, multiply, subtract, divide. The selected action can be performed on two columns, or one column and a fixed value, or a new column can be added. A target column for the result is specified. NB! if the target column already exist it will be overwritten, else it will be created. A common use is to create a unique Sample.Name from the existing Sample.Name column and e.g. the File.Name or File.Time columns. It can also be used to calculate the Amount from the Concentration.

Examples

Run this code

# Get a sample dataset.
data(set2)
# Add concatenate Sample.Name and Dye.
set2 <- columns(data = set2, col1 = "Sample.Name", col2 = "Dye")
# Multiply Height by 4.
set2 <- columns(data = set2, col1 = "Height", operator = "*", fixed = 4)
# Add a new column.
set2 <- columns(data = set2, operator = "&", fixed = "1234", target = "Batch")