cdfisocut − reduces dimensionality by taking a cut on a constant value of a field
cdfisocut { −t or −b }dimnametestvartestvalue
Cdfisocut expects a common data format file on the standard input and sends a common data format file to the standard output in which the dimensionality of fields depending on a specified dimension is reduced by one. This is accomplished by evaluating all such fields on a surface defined by a specified constant value of a test field. The command line argument "dimname" is the name of the dimension to be reduced. The last two arguments are respectively the name and value of the test field. The flags −b and −t determine whether the dimension to be cut is searched from low index to high (−b) or high index to low (−t) for the first occurence of the specified value of the test variable. This is useful when the test field is not monotonic in the reduced dimension. If the test value doesn’t occur at a particular location in the test field, bad data values are assigned to all reduced fields there.
kestrel%cdfisocut −t pressure theta 300 < input_file > output_file
In this example fields are evaluated over a surface defined by theta = 300. The dimension that is reduced is pressure.