Double or float assignment in C++

Using Arduino Programming Questions
1

The below works as a double, but not as a float. I can't figure out where to put the f to make float work.

int main()
{
    double TwelveRootTwo{ pow(2,1 / 12.00) };
   std::cout << "TwelveRootTwo = " << TwelveRootTwo << '\n';
}
2

In what way does it not work when you use float?

3

Replace double with float.

4

Since this is an Arduino forum, are you using a platform where float and double are different? On ESP32, where they are, consider

  auto flo = pow(2, (1/12.0f));
  auto dou = pow(2, (1/12.00));
  Serial.println(flo, 15);
  Serial.println(dou, 15);
  Serial.println(1/12.0f, 15);
  Serial.println(1/12.00, 15);
  Serial.println(sizeof(flo));
  Serial.println(sizeof(dou));
  auto ff3 = pow(2.0f, (1.0f/12.0f));
  Serial.println(sizeof(ff3));
  Serial.println(ff3, 15);

prints

1.059463096183108
1.059463094359295
0.083333335816860
0.083333333333333
8
8
4
1.059463143348694
5

No, that's what you did. He's asking what happened. In what way was it broken? What did you expect to happen? What actually happened? Compare and contrast the two.

6

This^^

I knew I needed to add an f to something... just wasn't sure what.
float TwelveRootTwo{ pow(2.0f,1.0f / 12.0f) };
Thanks!

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