---
name: "wcsgrid"
section: "1"
platform: "linux"
package: "wcslib-tools"
version: "8.4+ds-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/wcsgrid"
---

# wcsgrid(1)

Extract FITS WCS keywords and plot graticule

## NAME

wcsgrid - Extract FITS WCS keywords and plot graticule

## SYNOPSIS

**wcsgrid** \[*-a\<alt\>*\] \[*-d\<pgdev\>*\] \[*-h\<hdu\>*\] \[*\<fitsfile\>*\]

## DESCRIPTION

wcsgrid extracts the WCS keywords for an image from the specified FITS file and uses pgsbox() to plot a 2-D coordinate graticule for each alternate representation found.

The FITS file may be specified according to the syntax understood by cfitsio, for example "file.fits.gz+1" refers to the first extension (the second HDU) of a gzip'd FITS file.  Use "-" or omit the file name for input from stdin.

## OPTIONS

- **-a**\<alt\>

  Plot a graticule only for the alternate representation specified (ignored if there is only one).

- **-d**\<pgdev\>

  PGPLOT device type (default XWINDOW, use "?" for list).

- **-h**\<hdu\>

  Move to HDU number (1-relative) which is expected to contain an image array.  (Useful for input from stdin.)