rgr (version 1.0.4)

ltdl.fix.df: Replace Negative Values Representing Less Than Detects for a Data Frame

Description

Function to process a matrix or dataframe to replace negative values representing less than detects (<value) with positive half that value. This permits processing of these effectively categorical data as real numbers and their display on logarithmically scaled axes. In addition, some software packages replace blank fields that should be interpreted as NAs, i.e. no information, with zeros. The facility is provided to replace any zero values with NAs. In other instances data files have been built using an integer code, e.g., -9999, to indicate 'no data', i.e. the equivalent of NAs. The facility is provided to replace any so coded values with NAs. Any factor variables in the input matrix or data frame are passed to the output matrix or data frame. If a single vector is to be processed, use ltdl.fix A report of the changes made is displayed on the current device.

Usage

ltdl.fix.df(x, zero2na = FALSE, coded = NA)

Arguments

x

name of the matrix or dataframe to be processed.

zero2na

to replace any zero values with NAs, set zero2na = TRUE.

coded

to replace any numeric coded values, e.g., -9999 with NAs, set coded = -9999.

Value

• A matrix or dataframe identical to that input but where any negative values have been replaced by half their positive values, and optionally any zero values or numeric coded values have been replaced by NAs.

See Also

ltdl.fix

Examples

## Replace any missing data coded as -9999 with NAs and any remaining
## negative values representing less than detects with Abs(value)/2
data(fix.test)
fix.test
fix.test.fixed <- ltdl.fix.df(fix.test, coded = -9999)
fix.test.fixed

## As above, and replace any zero values with NAs
fix.test.fixed <- ltdl.fix.df(fix.test, coded = -9999, zero2na = TRUE)
fix.test.fixed