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Implicit Data Type Conversion

Many of the data I/O subroutines have the ability to perform implicit data type conversion. This means that the data type of the subroutine parameter does not need to be the same as the data type of the value in the FITS file. More specifically, the implicit data type conversion will be performed for b,i,j,e,f,d and g data types when getting a FITS header keyword value (FTGKYx and FTGKNx subroutines) and when putting or getting values to or from the primary array or a table. No checks for overflow conditions are performed during this forced datatype conversion. No data type conversion is performed when reading or writing string (s), logical (l), complex (c), or double complex (m) data types.