percentChange

percentChange(X, [n])

For each element X_i in X, return (X_i / X_i-n) - 1, representing the percentage changes between elements.

X is a vector or matrix.

n (optional) is an integer specifying the step to shift when comparing elements in X. The default value is 1, meaning to compare the current element with the adjacent element at left.

A vector or matrix with the same shape as X.

percentChange([1,2,3]);
// output: [,1,0.5]

percentChange(85 90 95);
// output: [,0.058824,0.055556]

m=matrix(100 105 109 112 108 116, 200 212 208 199 206 210);
m

percentChange(m);

r = percentChange(1..10,3);
r;
// output: [,,,3,1.5,1,0.75,0.6,0.5,0.43]

m=matrix(1 3 2 NULL 6 9 3, 0 8 NULL 7 6 2 8);
r = percentChange(m,2);
r;

m = 3 4 6 9
r2= percentChange(m,-2)
r2; 
// output: [-0.5,-0.56,,]