nullifeq

0     0     Edited Sep 1, 2015

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Usage 1:
[vector] x ← nullifeq( [vector]expr, [scalar]val₁[, [scalar]val₂... ] )

Returns vector x where:
x_i is set to null if expr_i equals any of val₁ ... val_N.
Otherwise x_i is set to expr_i.

This is commonly used to exclude values such as N/A or Don't Know from the base by converting e.g. 99's to null.

Examples:
nullifeq(income,99)
nullifeq(income,98,99)
pctin(nullifeq(income,98,99),1)


Usage 2:
[scalar]x ← nullifeq( [scalar]expr, [scalar]val )

Returns null if expr equals val.
Otherwise returns expr.

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