Gdl

From RHESSI Wiki

GDL is a free open-source version of IDL. Currently, GDL does all the features that IDL supports. For example, widgets in GDL are currently bleeding-edge. This guide is provided for those brave souls that are interested in exploring GDL and expanding it for the benefit of the community.

Contents 1 Installing GDL 1.1 Windows 1.2 Mac OS X 2 References

Installing GDL

The source code for GDL can be obtained from the GDL homepage. This source code needs to be compiled in order to create a gdl executable for whatever system you are using. Unfortunately, GDL uses many libraries (dependencies) which are not easily obtained or installed because of this each operating system requires a different approach depending on the tools available for that OS. This section provides one particular path to install for each operating system though others may also exist.

Windows

Compiling GDL under any windows therefore our solution to this problem is to install a virtual machine which itself runs some version of linux and install GDL inside this virtual machine. Our virtual machine of choice here is VirtualBox and our linux distribution will be fedora. Fedora earns our respect because GDL is included directly in its software installer.

1. Install Virtual box which can be found here. The VirtualBox Personal Use and Evaluation License (PUEL) provides all the functionality that you will need for GDL.
2. Next we must install Fedora 13 inside this virtual box. An easy install designed specifically for Virtual box can be found here. A small charge of $3 will give you access to an ftp download as well as the vboxguestadditions which provides seamless mode (fedora windows mingle with normal windows), and easy file sharing between your virtual box and windows.
3. Now start virtual box and create a new system with your fedora virtual box image.
4. Once it is install start your new fedora system. The default login and password for fedora is user and admin.
5. We can now easily install GDL by going to the system menu and choosing "add/remove software". You should install
   1. GDL
   2. GDL common tools
   3. CVS
   4. tcsh (our terminal of choice)
6. Next we need to configure GDL_PATH and GDL_STARTUP install ssw_gdl to work like ssw_idl - needed

Mac OS X

The source code for GDL can be obtained from the GDL homepage. This source code needs to be compiled in order to create a gdl executable. Unfortunately, GDL uses many libraries which are not available with a standard installation of Mac OS X. Some programs such as Macports can make this process easier and will automatically obtain all of the libraries necessary to compile GDL.

1. Install Apple's XCode. This will install many important libraries as well as install a compiler, gcc.
2. Install macports.
3. Run the following command which will (by default) install gdl in /opt/local/bin/

sudo port install gnudatalanguage

1. You should now be able to run gdl by typing "gdl" in the Terminal.

The next step is to set up SSWGDL. The following assumes that you already have an installation of SSW in /usr/local/ssw. If not go to the SSW installation page and follow the instructions.

1. Create a symbolic link to gdl with the following command.

ln -s /opt/local/bin/gdl /opt/local/bin/idl

References

• GDL - GNU Data Language
• SSWIDL
• SSW Installation Instructions