Binary floating point format
Binary floating point format
- Subject: Binary floating point format
- From: Carl Hoefs <email@hidden>
- Date: Thu, 30 Mar 2017 17:25:41 -0700
I have megabytes of raw legacy science datasets that I'm trying to read into my app and ingest into an array of doubles. The data is supposed to be organized as a stream of 8-byte doubles. I do not know how these datasets were generated, so I don't know what format (big/little endian, byte swapped, etc) they are in.
If I read the data directly into double variables, they evaluate as very small (E-92, etc).
I've tried all of these functions:
NSSwapDouble()
NSSwapBigDoubleToHost()
NSSwapLittleDoubleToHost()
NSConvertSwappedDoubleToHost()
CFConvertDoubleSwappedToHost()
The above functions generally return invalidly large values (E+87, etc).
Here is a hex dump of 4 binary doubles:
49BF7DE372533C05 A8C02FE3135B4F09 86C22FE37E630B05 27C2C4E3E258BA08
It seems there's some structure to them, as the last byte is always in the range of 03 to A0, so maybe they somehow correspond to IEEE 754 double-precision binary floating point format?
Is there yet another function I could use to parse this binary data?
-Carl
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