The following Fortran 77 program opens a file and reads vorticity and divergence spectral fields in GRIB format; it then calls INTUVP2 to create spectral U and V fields. Because of the preliminary call to INTOUT, the U and V fields are subsequently interpolated to grid-point fields with resolution 3deg 3 by 3deg 3 degrees without the need for a separate call to INTF. The function INTIN is not used here because the input fields are in GRIB format and are self-defining.
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