Normalization in variable range [ x , y ] in Matlab

Question

I wanna create basic matlab program that normalizes given array of integer in the given range.

• Inputs are an array [ a1 , a2 , a3 , a4 , a5 , a6 , a7... ], and the range [ x , y ]
• Output is normalized array.

But in everywhere, i see the normalization in the range of [0,1] or [-1,1]. Can't find variable range normalization. I will be grateful if you write the matlab code or the formula for variable range.

Thank you for ideas.

Answer 1

If you want to normalize to [x, y], first normalize to [0, 1] via:

 range = max(a) - min(a);
 a = (a - min(a)) / range;

Then scale to [x,y] via:

 range2 = y - x;
 a = (a * range2) + x;

Putting it all together:

 function normalized = normalize_var(array, x, y)

     % Normalize to [0, 1]:
     m = min(array);
     range = max(array) - m;
     array = (array - m) / range;

     % Then scale to [x,y]:
     range2 = y - x;
     normalized = (array*range2) + x;

Answer 2

Starting from R2017b, MATLAB has this function named rescale which does exactly this.
i.e. if you want to rescale array to the interval [x, y] then:

normalized_array = rescale(array, x, y);

If x and y are not specified then array gets normalized to the interval [0,1].