Re: Reading Float Data from a binary file into ada

frikk a écrit :
Hello everyone! I am having a problem that I would love some help with.

Essentially I was given a Visual Basic program that dumps a binary configuration file with all of the variables in a set. The variables are each 32 bit floats, with the first 16 bits being the integer part and the second 16 bits being a representation of the fraction (I'm not sure if this is stanard - but its just how VB dumps the data).
Hmm... This looks like a fixed point representation, not a floating point one.

The binary dump is basically a copy of the way VB stores the data in memory. I need to be able to use this data in ada. There is a C counterpart to this that makes use of a 'union' to grab the data 1 byte (8 bits) at a time, put them into a char array of size 4, then use a 32 bit float to reference the data. Is there somehow I can do this in ada as well?
In general, Unchecked_Conversion is your friend when you need two different views, at differing levels of abstraction, of the same data.

Basically I need to be able to read in the binary data byte by byte but store it into a 32 bit Float.
However, if you do an unchecked_conversion to Float, it will certainly not work, because your data don't look at all like floats!

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