Environment Variables

GR and GKS can be configured using a number of environment variables. The following table lists these environment variables and their effects. For information on how to set an environment variable, see the sections below.

Variable

Description

GRDIR

Path to the GR installation directory

Example: /usr/local/gr/

GRLIB

Path to the GR library directory

Example: /usr/local/gr/lib

GKS_FONTPATH

Path to the GKS fonts directory

Example: /usr/local/gr/fonts

GKS_FILEPATH

Path to the file GKS should write its output to

Example: output.png

GKS_CONID

File descriptor GKS should write its output to

Example: 1

GKS_WSTYPE

Default workstation type

Example: png

See also: Workstation Types

GKS_ENCODING

Input encoding used for GKS functions

Example: UTF-8

See also: Encoding Support

GKS_DOUBLE_BUF

Only draw when gr_updatews() is called

GKS_USE_GS_BMP

Use the gsplugin for BMP output instead of the cairoplugin

See also: File Formats

GKS_USE_GS_JPG

Use the gsplugin for JPEG output instead of the cairoplugin

See also: File Formats

GKS_USE_AGG_JPG

Use the aggplugin for JPEG output instead of the cairoplugin

See also: File Formats

GKS_USE_GS_PNG

Use the gsplugin for PNG output instead of the cairoplugin

See also: File Formats

GKS_USE_AGG_PNG

Use the aggplugin for PNG output instead of the cairoplugin

See also: File Formats

GKS_USE_GS_TIF

Use the gsplugin for Tiff output instead of the cairoplugin

See also: File Formats

GKS_QT_USE_CAIRO

Use the cairoplugin for rendering in the qtplugin and gksqt

See also: Integrations

GKS_QT_USE_AGG

Use the aggplugin for rendering in the qtplugin and gksqt

See also: Integrations

GKS_PGF_ONLY_CONTENT

Do not write a full TeX document, instead write only definitions and TikZ picture

GKS_PDF_PREVIEW_FIX

Render images using filled rectangles to workaround a problem with Apple’s Preview app, which generally uses bilinear interpolation when rendering images, resulting in blurred output, e.g. when displaying heatmaps

GKS_VIDEO_OPTS

Resolution and framerate when using the videoplugin

Example: 1920x1080@60

See also: Configuring Video Output Options

GKS_GKSQT_PREVENT_RESIZE

Prevent automated resizing in gksqt

GKS_QT_VERSION

Qt version to use in the qtplugin

Example: 5

GKS_NO_EXIT_HANDLER

Do not set an exit handler

GKS_DISABLE_PAGE_SUFFIX

Do not add a page suffix to the file name when writing more
than once to a file which does not natively support pagination.

GKS_DEFAULT_RESAMPLE_METHOD

The default method for resampling image data in raster based
workstation types. Can be nearest, linear or lanczos.

Example: nearest

GR_SKIP_RUNTIME_VERSION_CHECK

Skip runtime version checks in the gr Python package

Setting Environment Variables on macOS or Linux

To set an environment variable in a shell on macOS or Linux, you can use:

export VARIABLE_NAME=value

Alternatively, for running a single command with the variable set, you can also use:

VARIABLE_NAME=value command

Setting Environment Variables on Windows

To set an environment variable in cmd.exe on Windows, you can use:

set VARIABLE_NAME=value

Setting Environment Variables in Programs

Many programming languages offer ways to set environment variables as well:

import os

os.environ["VARIABLE_NAME"] = "value"
#include <stdlib.h>

/* ... */

setenv("VARIABLE_NAME", "value", 1);
ENV["VARIABLE_NAME"] = "value"