IN: Sign position, i.e., the bit offset of the floating-point sign bit.
IN: Exponent bit position.
IN: Size of exponent in bits.
IN: Mantissa bit position.
IN: Size of mantissa in bits.
H5Tset_fieldssets the locations and sizes of the various floating-point bit fields. The field positions are bit positions in the significant region of the datatype. Bits are numbered with the least significant bit number zero.
Fields are not allowed to extend beyond the number of bits of precision, nor are they allowed to overlap with one another.
Returns a non-negative value if successful; otherwise returns a negative value.