Float value convert to hex and All hex bit addition

Projects Programming
1

I want to convert float value to hex value and required the sum of all bits.

2

Computers use binary mathematics. To compute the sum of the bits representing a floating point number, simply add up those bits.

"Hex" is a human readable representation of a binary number, like decimal but with 16 as the number base.

3

Serial.begin(9600);
float f = 58.5;
Serial.print("0x");
Serial.println((uint32_t)&f, HEX);

Output 0x426A0000.
I want to Add 42+6A

4

...and that's why you use code tags for posting code.
(What's stopping you adding those four bytes together?)

5

This does not convert a float to hex, it converts the address of variable f to an integer and prints it.

6

No, the asterisk is there,but the lack of code tags converted it to italics

7

Oh, I see.

In that case, the snippet invokes undefined behaviour because of the strict aliasing rules.

8

sorry but add 42+6A+00+00

9

Yes, that's right.

10

The following, very icky, method should work:

float f {58.5};

uint32_t sum {0};
for (size_t i {0}; i < sizeof(float); ++i) {
  sum += reinterpret_cast<uint8_t const* const>(&f)[i];
}

Serial.println(sum);  // Prints "172".

[edit]

If you want to have something that works for other types as well, you could consider the following:

template <class T> uint32_t byteSum(T const& data) {
  uint32_t sum {0};
  for (size_t i {0}; i < sizeof(T); ++i) {
    sum += reinterpret_cast<uint8_t const* const>(&data)[i];
  }
  return sum;
}

Usage:

Serial.println(byteSum(f));  // Prints "172";
11

something like this..

  uint8_t* b = (uint8_t *)&f;
  uint16_t sum;
  for (int i = 0; i < sizeof(float); i++) {
    sum += *b;
    b++;
  }

good luck.. ~q

12

Something like this:

void setup()
{
  Serial.begin(9600);
  float y = 58.5;
  byte *ptr;
  ptr = (byte*)&y;
  uint16_t sum = 0;
  for(int i = 0; i< 4; i++, ptr++)
  {
    sum += *ptr;
  }
  Serial.println(sum, HEX); //shows: AC
  //---for manual verification-----
  float y1 = 58.5;
  long *ptr1;
  ptr1 = (long*)&y1;
  long m = *ptr1;
  Serial.println(m, HEX); //show: 426A0000
}

void loop()
{
  
}
13

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