Re: ATAN function with two ARGS

[davidf(at)dfanning.com (David Fanning)]

Ben Tupper (tupper@seadas.bigelow.org) writes:

> If this argument is supplied, ATAN returns the angle whose tangent
> is equal to Y/X. If both arguments are zero, the result is undefined.

Notice they don't say the "result of the function" is
undefined. If they did, I could understand your confusion.
But here they have made a truthful and accurate statement.
*Implying* that they were talking about the result of the
function is an old technical writers trick that allows one
to remain truthful, while still confusing the rift-raft.

You have to read this documentation *much* more carefully, 
Ben, if you have any hopes of winning a commission 
in the IDL Expert Programmers Association. :-)

Cheers,

David
-- 
David Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438 E-Mail: davidf@dfanning.com
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