This Fortran function is used to describe the input field.
If the field is in GRIB format, its internal definition contains all the information about the field necessary for interpolation and there is no need to use INTIN.
If the input field is an array of Fortran real number values, the function may have to be called several times to build up its description. There are default values for parts of the description which may save some calls.
Declare the function as INTEGER and EXTERNAL, and invoke it as follows:
IRET = INTIN( HPARN, INTV, REALV, CHARV)
Character strings and single integer values may be used directly in calls:
IRET = INTIN( 'form', INTV, REALV, 'unpacked')
IRET = INTIN( 'gaussian', 80, REALV, CHARV)
with simple dummy variables (IDUM, RDUM and CDUM say) in place of the unused array arguments:
IRET = INTIN( 'form', IDUM, RDUM, 'unpacked')
IRET = INTIN( 'gaussian', 80, RDUM, CDUM)
If a series of unpacked fields are interpolated, it is necessary to call INTIN between fields to ensure correct handling. For example, if U, V, T, U, V, T, ... fields are processed, `usewind' must be `yes' for U and V; then `no' for T; then `yes' for U and V; then `no' for T; and so on.
It is important to check the return value in IRET is 0 to ensure the call has been successful.
This is the list of possible parameters: