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How can I store float variable to int array (C)?

Is there a way to store float variable for example: PI (3.1415) to int16_t array, and then print it using pointers?

Solution

  • This is how you can do it w/ pointer casting:

    float f = 3.14; // float -> 4 bytes
int16_t i[2];   // int16_t -> 2 x 2 bytes each

i[0] = *(((int16_t *)&f) + 0);
// store first 2 bytes of float into i[0]
// be careful here!!! endianness matters
// for little endian, use
// i[0] = *(((int16_t *)&f) + 1);

i[1] = *(((int16_t *)&f) + 1);
// store last 2 bytes of float into i[1]
// be careful here!!! endianness matters
// for little endian, use
// i[1] = *(((int16_t *)&f) + 0);

printf("%d\n", (int)i[0]);
// prints the int16_t representation 
// of the first 2 bytes of float bit pattern
printf("%d\n", (int)i[1]);
// prints the int16_t representation 
// of the last 2 bytes of float bit pattern

printf("%f\n", *((float *)&i));
// prints the float in full