---
name: "plstransform"
section: "3plplot"
platform: "linux"
package: "plplot-doc"
version: "5.15.0+dfsg2-15"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/plstransform"
---

# plstransform(3plplot)

Set a global coordinate transform function

## NAME

**plstransform** - Set a global coordinate transform function

## SYNOPSIS

**plstransform**(*coordinate\_transform*, *coordinate\_transform\_data*)

## DESCRIPTION

This function can be used to define a coordinate transformation which affects all elements drawn within the current plot window.  The *coordinate\_transform* callback function is similar to that provided for the [**plmap**(3plplot)](/plmap/3plplot.md) and [**plmeridians**(3plplot)](/plmeridians/3plplot.md) functions.  The *coordinate\_transform\_data* parameter may be used to pass extra data to *coordinate\_transform*.

Redacted form: General: **plstransform(coordinate\_transform, coordinate\_transform\_data)**

This function is used in examples 19 and 22.

## ARGUMENTS

- *coordinate\_transform* (**PLTRANSFORM\_callback**(3plplot), input)

  A callback function that defines the transformation from the input (x, y) world coordinates to new PLplot world coordinates.  If *coordinate\_transform* is not supplied (e.g., is set to NULL in the C case), then no transform is applied.

- *coordinate\_transform\_data* (**PLPointer**(3plplot), input)

  Optional extra data for *coordinate\_transform*.

## AUTHORS

Many developers (who are credited at http://plplot.org/credits.php) have contributed to PLplot over its long history.

## SEE ALSO

PLplot documentation at http://plplot.org/documentation.php.