Environment variables used by Sage

Sage uses several environment variables when running. These all have sensible default values, so many users won’t need to set any of these. (There are also variables used to compile Sage; see the Sage Installation Guide for more about those.)

• DOT_SAGE – this is the directory, to which the user has read and write access, where Sage stores a number of files. The default location is ~/.sage/, but you can change that by setting this variable.
• SAGE_RC_FILE – a shell script which is sourced after Sage has determined its environment variables. This script is executed before starting Sage or any of its subcommands (like sage -i <package>). The default value is $DOT_SAGE/sagerc.
• SAGE_STARTUP_FILE – a file including commands to be executed every time Sage starts. The default value is $DOT_SAGE/init.sage.
• SAGE_SERVER – only used for installing packages. Alternative mirror from which to download sources, see the Installation Guide for details.
• SAGE_PATH – a colon-separated list of directories which Sage searches when trying to locate Python libraries.
• SAGE_BROWSER – on most platforms, Sage will detect the command to run a web browser, but if this doesn’t seem to work on your machine, set this variable to the appropriate command.
• SAGE_ORIG_LD_LIBRARY_PATH_SET – set this to something non-empty to force Sage to set the LD_LIBRARY_PATH before executing system commands.
• SAGE_ORIG_DYLD_LIBRARY_PATH_SET – similar, but only used on Mac OS X to set the DYLD_LIBRARY_PATH.
• SAGE_CBLAS – used in the file SAGE_ROOT/src/sage/misc/cython.py. Set this to the base name of the BLAS library file on your system if you want to override the default setting. That is, if the relevant file is called libcblas_new.so or libcblas_new.dylib, then set this to “cblas_new”.