Re: undefined variable problem

On 2007-03-30, John Appleyard <spamtrap@xxxxxxxxxxxxxx> wrote:

Check out Catherine's reply again. I think you may have misunderstood
what the compiler means by "undefined". It doesn't mean "not allocated"
or "not declared" or "not associated". It means "used before set" -
i.e. no value has been assigned to a since it was created (by allocation
or whatever). It is an error to use the value of a variable if it has
never been given a value, and that is what the compiler is complaining
about.

Hmm... now that I think of it... i've fixed a problem that made
the error go away... maybe it is what you are mentioning here...

The situation I have basically boils down to the following: I
allocated a rank 2 array (representing a matrix), and i only
assigned values to the *lower triangular part*. My application
required the *upper triangular part without the diagonal* to be
zero... but i forgot to
explicitly set that part to zero... so after allocation and setting
the lower triangular part, I couldn't be sure that the values in the
upper triangular part were zero...

Could it be that the NAGWare f95 compiler was smart enough to
detect that the *upper triangular part* of the rank2 array
(matrix) that I was using was not initialised and therefore
reported the error?

Best wishes,
Bart

--
"Share what you know. Learn what you don't."
.

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