Geometric mean bit hack

Gallery
1 
// Bit hack fast geometric mean
void setup() {
  float m1=300f;
  background(0);
  size(500, 500);
  stroke(255, 0, 0);  // red
  for (int i=0; i<500; i++) {
    point(i, 499-sqrt(m1*i));
  }
  stroke(0, 255, 0);  // green
  for (int i=0; i<500; i++) {
    float f=i;
    int j=Float.floatToRawIntBits(f);
    int k=Float.floatToRawIntBits(m1);
    j=(j+k)>>>1;  
    float p=Float.intBitsToFloat(j);
    point(i, 499-p);
  }
}
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2

Nice! Thanks for sharing. Your post brought me also to this link.

3

Thanks for the link. Floating point bit hacks are very useful for experimenting with neural network activation functions. If you just want a little bit of nonlinarity for example you can multiply the approximate square root of a number by itself.
Or if you want to convert 2 numbers from the Gaussian probability distribution to a number from the uniform distribution you can use atan2(x,y).

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