GrADS Function: coll2gr

## coll2gr()

This function creates a grid from a collection of station data. The syntax is:

`coll2gr(cnum <,num>)`

`cnum` collection number
`num` number of vertical levels in the output grid (default is 10)

If `num` is given as `"-u"`, then the vertical levels will be a union of all the levels in the collection of station data.

### Usage Notes

1. Before using `coll2gr`, you must create the collection of stations using the GrADS command `collect`.

2. `coll2gr` does not yet support time slices; currently, it will only work when the collection of stations is a collection of vertical profiles.

3. `coll2gr` produces an output grid that varies in X and Z; the dimension environment used when `coll2gr` is invoked must also be X and Z varying. The X axis of the output grid will contain the equally spaced station profiles and will span the range of the current X dimension environment. The Z axis of the output grid will span the range of the current Z dimension environment and will have either the specified number of levels or a union of the levels. Data points outside of the range of levels will be used for interpolating to within the range if appropriate.

4. The `"-u"` option will only work for data in pressure vertical coordinates. If your vertical coordinate is height, `num` should be the actual number of vertical levels in the collection of profiles. Note: This restriction has been removed as of version 2.1.0.

5. See the section of the User's Guide on Arbitrary Cross Sections for more information.

### Examples