Sparse arrays vs full arrays

Benchmark created by Mattias Ernelli on

Setup

var n, N, i, I, sparse = [],
      full = [],
      full2 = [];
  
  N = 16384;
  I = 8;
  
  for (i = 0; i < I; i++) {
    do {
      n = (N * Math.random()) | 0;
      if (n > (N - 1)) {
        n = N - 1;
      }
    } while (sparse[n]);
    sparse[n] = -100 + 200 * Math.random();
  }
  full.length = N;
  full2.length = N;
  for (i = 0; i < N; i++) {
    if (typeof sparse[i] === "number") {
      full[i] = sparse[i];
      full2[i] = sparse[i];
    } else {
      full[i] = 0;
      full2[i] = -100 + 200 * Math.random();
    }
  }

Test runner

Ready to run.

Testing in
TestOps/sec
Sparse array sum
var sum = 0;
sparse.forEach(function(v, i) {
  sum += v;
});
ready
Full array sum
var len = full.length;
sum = 0;
for (i = 0; i < len; i++) {
  sum += full[i];
}
ready
Running sparse on full array
var sum = 0;
full.forEach(function(v, i) {
  sum += v;
});
ready
Sum all elements on a full array without zeros
var len = full2.length;
sum = 0;
for (i = 0; i < len; i++) {
  sum += full2[i];
}
ready

Revisions

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