# Sparse arrays vs full arrays

## JavaScript performance comparison

Revision 11 of this test case created by

## Preparation code

``````

<script>
Benchmark.prototype.setup = function() {
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();
}
}

console.log(sparse);
console.log(full);
console.log(full2);

};

</script>
``````

## Test runner

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
Sparse array sum
``````var sum = 0;
sparse.forEach(function(v, i) {
sum += v;
});``````
pending…
Full array sum
``````var len = full.length;
sum = 0;
for (i = 0; i < len; i++) {
sum += full[i];
}``````
pending…
Running sparse on full array
``````var sum = 0;
full.forEach(function(v, i) {
sum += v;
});``````
pending…
Sum all elements on a full array without zeros
``````var len = full2.length;
sum = 0;
for (i = 0; i < len; i++) {
sum += full2[i];
}``````
pending…

## Revisions

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