casting - C Function to Convert float to byte array -

i'm trying make function accept float variable , convert byte array. found snippet of code works, reuse in function if possible.

i'm working arduino environment, understand accepts c language.

currently works:

float_variable = 1.11; byte bytes_array[4];  *((float *)bytes_array) = float_variable; 

what can change here make function work?

float float_test = 1.11; byte bytes[4];  // calling function float2bytes(&bytes,float_test);  // function void float2bytes(byte* bytes_temp[4],float float_variable){       *(float*)bytes_temp = float_variable;   } 

i'm not familiar pointers , such, read (float) using casting or something?

any appreciated!

cheers

*edit: solved

here's final function works in arduino finds this. there more efficient solutions in answers below, think okay understand.

function: converts input float variable byte array

void float2bytes(float val,byte* bytes_array){   // create union of shared memory space   union {     float float_variable;     byte temp_array[4];   } u;   // overite bytes of union float variable   u.float_variable = val;   // assign bytes input array   memcpy(bytes_array, u.temp_array, 4); } 

calling function

float float_example = 1.11; byte bytes[4];  float2bytes(float_example,&bytes[0]); 

thanks everyone's help, i've learnt pointers , referencing in past 20 minutes, cheers stack overflow!

easiest make union:

#include <stdio.h>  int main(void) {   int ii;   union {     float a;     unsigned char bytes[4];   } thing;    thing.a = 1.234;   (ii=0; ii<4; ii++)      printf ("byte %d %02x\n", ii, thing.bytes[ii]);   return 0; } 

output:

byte 0 b6 byte 1 f3 byte 2 9d byte 3 3f 

note - there no guarantee byte order… depends on machine architecture.

to function work, this:

void float2bytes(byte* bytes_temp[4],float float_variable){    union {     float a;     unsigned char bytes[4];   } thing;   thing.a = float_variable;   memcpy(bytes_temp, thing.bytes, 4); } 

or hack it:

void float2bytes(byte* bytes_temp[4],float float_variable){    memcpy(bytes_temp, (unsigned char*) (&float_variable), 4); } 

note - in either case make sure copy data location given input parameter. crucial, local variables not exist after return (although declare them static, let's not teach bad habits. if function gets called again…)