Re: Problems with num function

Hi Katie,

The "num" function doesn't count the number of values in an array. It
counts the locations in an array where the values evaluate to "True".

One of the values in your array is equal to 0, which evaluates to
False. So, even though you have 20 values, only 19 of them are
"True", and hence "num" returns 19.

I think you want to use "dimsizes" instead of "num".

--Mary

On Tue, 12 May 2009, Katie Holman wrote:

> Hi All,
>
> I would like to bring attention to a simple problem I am encountering
> with the num function. I have a script written that is summing up the
> number of individual months in my data file. The total number of time
> elements is 240 - so there are 20 Jan., 20 Feb., etc.
>
> The command below produces a list of twenty values.
>
> print(ind(month.eq.1))
>
> (0) 0
> (1) 12
> (2) 24
> (3) 36
> (4) 48
> (5) 60
> (6) 72
> (7) 84
> (8) 96
> (9) 108
> (10) 120
> (11) 132
> (12) 144
> (13) 156
> (14) 168
> (15) 180
> (16) 192
> (17) 204
> (18) 216
> (19) 228
>
> When I count the number of times a month number of 1 occurs, the
> function num only catches 19 of them. The command line is below.
>
> print(num(ind(month.eq.1)))
>
> (0) 19
>
> I have gotten around the problem by instead using dimsizes, but I
> thought everyone should be aware of the issue.
>
> Thank you,
>
> Katie Holman
> UW-Madison
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Received on Wed May 13 2009 - 08:38:41 MDT