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Re: checking if variable is defined

Dominik (dpaul@ukl.uni-freiburg.de) writes:

> I would like to plot a variable, but only if it is existing. When the
> Variable is undefined, nothing should happen. So I am searching for an
> expression for the if  statement. Does anybody know an expression like:
> if ( vaiable_name existing) then...

  IF N_Elements(variable_name) NE 0 THEN doSomething



David Fanning, Ph.D.
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