8-byte double to 32-bit float

i have problem read binary data serial line, byte byte. no problem fix integers since same size, doubles sent other applications 8 bytes (64 bits), whereas float (or double) in arduino 32 bits.

the data read little endian , ieee754 standard, it's described @ http://en.wikipedia.org/wiki/double_precision_floating-point_format. have not succeded in converting, thought should ask here if has function can or knows can more information. you?

i not care loosing decimals @ end; not work nuclear safety.

looking @ 2 formats on wikipedia, 32 bit floats have: 1 sign bit, 8 exponent , 23 fraction bits.

whereas 64 bit floats have: 1 sign bit, 11 exponent , 52 fraction bits.

i might wrong this, guess if packed sign bit of 64bit float sign bit of 32bit float , significant 8 bits of 64bit floats exponent 32bit float's exponent bit positions , same significant bits of fraction part, might work!

what bit hazy (my c's not good) how packing. guess, might able set bits in int[2] array (32 bit) , assign double variable it?

something (although may talking java):
int rawbits = int[2];
// loops bit copying
double value = (double)rawbits;

hope @ least points in right direction.

si.

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