| Re: Access array elements with String [message #61364 is a reply to message #61363] |
Mon, 14 July 2008 08:41  |
![Bob[3] is currently offline](theme/default/images/xoffline.png.pagespeed.ic.XRkd1fkXye.png "Bob[3] is currently offline")
Bob[3]
Messages: 60
Registered: December 2006
|
Member |
|
|
On Jul 14, 11:16 am, humanumbre...@gmail.com wrote:
> Hello all,
>
> Another issue - perhaps one of you has encountered this before. It's
> sort of a neat problem. I'm attempting to build array subscripts on
> the fly based on user input. IE the number of static/variable elements
> is changing, which allows the user to pick different axes to plot.
> Nevermind all that.
>
> Anyway, let's say a user wants a particular axis to be variable. In
> this case, the dataset array where I'm attempting to pull values from
> would contain a *, to get all these elements. Unfortunately, I do not
> know in advance which dimension of the array I will be using, so I am
> attempting to build the subscript based on a string.
>
> This was my original thought:
> a = dindgen(5,5,5)
> b = ['3','3','3']
> print, a[b]
> but this just returns a[3], a[3], a[3]
>
> So, I figured I'd do it this way:
> c = '3'
> print, a[c,c,c] -- This works!
>
> Now for the gold,
> d = '*'
> print, a[c,c,d] -- error - can't convert string-> long
> so I get an idea-- maybe I'll just use the ascii value for the
> asterisk.
> d = String(42b)
> print, a[c,d,d] -- error - can't convert string-> long
>
> Any thoughts ?
> Thanks in advance
> --Justin
Why try to force the '*' - might not SIZE be more useful?
e.g.
s=SIZE(a)
print, a[c,c,s[3]] ; for a[c,c,d]
print, a[c,s[2],s[3]]; for a[c,d,d]
|
|
|
|
comp.lang.idl-pvwave archive
Members
Search
Help
Login
Home
