Format p-values for display

Convert p-values to a compact textual representation. The function prints decimals up to the first non-zero decimal and the following one, applying standard rounding.

Usage

show.p(p, add.p = FALSE)

Arguments

p

a value or vector of the p-value(s) to be shown, where \(0<p<1\).

add.p

logical indicating whether the text p= (or p<, if it applies) should be added before the p-value.
The default value is FALSE.

Value

A character vector with the formatted p-values.

Details

The number of decimals shown depends on the magnitude of the p-value so that two meaningful digits are displayed after the leading zeros.

Specifically:

• For \(p \ge 0.1\), two decimal places are shown.

• For \(0.01 \le p < 0.1\), three decimal places are shown.

• For \(0.001 \le p < 0.01\), four decimal places are shown.

• For \(0.0001 \le p < 0.001\), five decimal places are shown.

• For \(p < 0.0001\), the string "<0.0001" is returned.

This formatting ensures that the first non-zero decimal of the \(p\)-value and the following digit are displayed, while avoiding an excessive number of leading zeros.

If add.p = TRUE, the prefix "*p*=" (or "*p*<" when applicable) is added to the formatted value. This will ensure the p appears in cursive when calling the function in line on R markdown documents.

Examples

show.p(0.00785)
show.p(c(0.03042, 0.1579, 0.0000025))
show.p(0.00785, add.p = TRUE)
show.p(c(0.03042, 0.1579, 0.0000025), add.p = TRUE)