Re: Reading Float Data from a binary file into ada

Steve wrote:

The following snippet contains the pieces you need to do the conversion.

TYPE aByte IS MOD 256;

FOR aByte'SIZE USE 8;

TYPE aByteArray IS ARRAY( Positive RANGE <> ) OF aByte;

PRAGMA PACK( aByteArray );

TYPE aFourBytes IS NEW aByteArray(1..4);

FUNCTION Conv IS NEW Ada.Unchecked_Conversion( aFourBytes, float );

...

a : float;
b : aFourBytes;

...

a := Conv( b )

Use unchecked conversion to convert from a type that contains 4 bytes to the float value you're looking for.

You have typed lots of lines of code to ensure that 4 bytes are treated as 4 bytes, but you did not provide any guarantee that Float has 4 bytes as well. You *can* rely on some assumptions about your compiler, but having these assumptions already in place anyway, is there a way to make the conversion simpler? Cannot you just read four bytes from the file directly to the Float variable using for example sequential or direct I/O?


--
Maciej Sobczak : http://www.msobczak.com/
Programming : http://www.msobczak.com/prog/
.