Specifies the number of fields the request is expected to retrieve.


Some datasets might have gaps, e.g. not all parameters are archived at all levels or all steps. In such cases MARS cannot determine the correct number of fields to retrieve and will issue a warning or error. To avoid that, the keyword expect can be set to specify the exact number of fields to be retrieved.

Suppose a dataset only had parameter geopotential at 1000/500 and temperature at 850 archived, the request should look like follows:


param = 129/130, levelist = 1000/850/500, expect = 3,

If expect=any is provided, MARS will retrieve any number of fields or observations for the given request, but it will not fail if some data is not found. In case no data is found, an empty target file is produced.

In general, the use of expect=any is discouraged.


Not supported.