Gabriel: Die Seite wurde neu angelegt: „IDL (Interactive Data Language) is a commercial "programming language" that is used for example in astro- and plasma-physics. The current version is developed…“

2016-08-24T17:42:33Z

Die Seite wurde neu angelegt: „IDL (Interactive Data Language) is a commercial "programming language" that is used for example in astro- and plasma-physics. The current version is developed…“

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IDL (Interactive Data Language) is a commercial "programming language" that is used for example in astro- and plasma-physics. The current version is developed and sold by Exelisvis (http://www.exelisvis.com).

An alternative that should be widely compatible is the GNU Data Language GDL that can be used for free (http://gnudatalanguage.sourceforge.net/).

==Installation etc.==
===GDL Installation===

to build library: netcdf with fpic

cmake with -DPYTHON_MODULE=On

===GDL and Python===

===/CECL Keyword===

The /CECL keyword is currently (version 0.9.5) not supported by GDL. Anyway, the GDL documentation states that this keyword is only important to Windows users. So I just removed that keyword in function calls (calls to external functions) without experiencing any problems.

==Programming==

===Concatenating Strings and other Datatypes===
In IDL/GDL the string datatype can be used easily by setting variables the following way:
<syntaxhighlight lang=bash>x = 'text'
</syntaxhighlight>
In order to build up strings out of different phrases the '+' is used to concat them:
<syntaxhighlight lang=bash>x = 'text'
y='another text'
print, x+y
</syntaxhighlight>
will print out 'textanother text'.

The same can be done with other datatypes when they are converted to the string datatype by means of the STRING() function:
<syntaxhighlight lang=bash>x = 'text'
y=4.0
print, x+STRING(y)
</syntaxhighlight>
Anyway, the print-out format will not be what you expect:
<syntaxhighlight lang=bash>text 4.00000
</syntaxhighlight>
In order to get rid of the spaces, the STRTRIM() function can be used.

==Troubleshooting==
===IDL runs fine but some standard procedures and functions are not found===
Strangely, IDL might run fine but complain from time to time when some included functions are called. In my case this happened when I wanted to use the coyote libraries for plotting. The solution is to make sure that the IDL library directory is in your IDL path:
<syntaxhighlight lang=bash>echo $IDL_PATH
</syntaxhighlight>
If there is not something like /usr/share/itt/idl/idl6.4/lib in that path (version and distributor may be different) then add it. One option is to put
<syntaxhighlight lang=bash>export IDL_PATH=/usr/share/itt/idl/idl6.4/lib:$IDL_PATH
</syntaxhighlight>
at the end of your /home/username/.bashrc file.

IDL Programmierung - Versionsgeschichte

Gabriel: Die Seite wurde neu angelegt: „IDL (Interactive Data Language) is a commercial "programming language" that is used for example in astro- and plasma-physics. The current version is developed…“