GrADS Command: query

## query

The `query` command allows the user to get information about a variety of aspects of the current GrADS session. Configuration, plot characteristics, graphics specifics, and file structure are some examples. The use of `query pos` combined with the coordinate transformations is the basis of many interactive applications with buttons and drop menus. The `query` command may be shortened to simply `q`. The syntax is:

`query <option>`
or
`q <option>`

When given without an `option`, the `query` command returns a list of the possible options. These are:

> attr n | Returns all attributes for file n (or default file if n is omitted)
> cache n | Returns netcdf4/hdf5 cache size for file n (or default file if n is omitted) (2.0.a8+)
> cachesf | Returns netcdf4/hdf5 cache scale factor (2.0.a8+)
> calendar | Returns calendar mode: unset, 365-day, or standard
> config | Returns GrADS configuration information
> contours | Returns colors and levels of a line contours (2.0.a8+)
> ctlinfo | Returns contents of data descriptor file
> dbf | Lists the contents of a shapefile attribute database (2.0.a8+)
> define | Lists currently defined variables
> defval v1 i j | Returns the value of defined variable `v1` at point `i,j`
> dialog args | Launches a dialog box that prompts for text or numeric data entry
> dims | Returns current dimension environment
> ens | Returns ensemble metadata
> file n | Returns info on file number `n`
> files | Lists open files
> fwrite | Returns status and characteristics of fwrite ouput file
> gxinfo | Returns graphics environment info
> gxout | Returns current gxout settings
> lats | Returns the status of the GrADS-LATS interface
> pos | Waits for mouse click, then returns position plus additional widget information
> sdfwrite | Returns the status of the sdfwrite options
> shades | Lists colors and levels of shaded contours
> shp | Lists the contents of a shapefile (2.0.a8+)
> shpopts | Returns settings for drawing and writing shapefiles (2.0.a9+)
> string str | Returns the width of string `str` in virtual page inches
> time | Returns info about time settings
> udft | Returns the user defined function table
> undef | Returns the output undefined value
> xinfo | Returns characteristics of the graphics display window
> xy2w v1 v2 | Converts XY coords to world coords
> xy2gr v1 v2 | Converts XY coords to grid coords
> w2xy v1 v2 | Converts world coords to XY coords
> w2gr v1 v2 | Converts world coords to grid coords
> gr2w v1 v2 | Converts grid coords to world coords
> gr2xy v1 v2 | Converts grid coords to XY coords
> pp2xy v1 v2 | Converts virtual page XY coords to real page XY coords

``

### Usage Notes

For more information on the use of the `query` command, see the section of the User's Guide on commands that complement the scripting language.

### Examples