Element by element missing value tests of data objects.
Syntax: @eisna(m)
m: numeric or alphanumeric object
Return: vector or matrix object
Returns a test for whether the elements in the data object m are numeric missing values, or empty strings.
Each element of the returned matrix is equal to 1 or 0 depending on the outcome of the comparison. Missing values are set to 1, and non-missing are set to 0.
Examples
Let X be an
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matrix. Then
= @eisna(X)
returns an
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binary matrix indicating places where X is missing.
Cross-references
See also
@enisna,
@ege,
@egt, and
@elt.