util.trigamma {MAnorm2}

Utility Trigamma Function

Description

util.trigamma is essentially the same as the trigamma function but is for being consistent with the inv.trigamma function at very small or very large input values.

Usage

util.trigamma(y)

Arguments

y

A positive numeric scalar. Inf is allowed.

Value

A positive numeric scalar, which is essentially the same as trigamma(y) but could be a little different at very small or very large y values.

See Also

inv.trigamma for an implementation of the inversion of the trigamma function.

Examples

trigamma(1:6)
vapply(1:6, util.trigamma, numeric(1))

trigamma(1e-4)
util.trigamma(1e-4)

trigamma(1e8)
util.trigamma(1e8)

trigamma(Inf)
util.trigamma(Inf)