diff options
Diffstat (limited to 'src/pkg/math/rand/rand_test.go')
| -rw-r--r-- | src/pkg/math/rand/rand_test.go | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/src/pkg/math/rand/rand_test.go b/src/pkg/math/rand/rand_test.go index bbd44e3f8..4d3abdb60 100644 --- a/src/pkg/math/rand/rand_test.go +++ b/src/pkg/math/rand/rand_test.go @@ -57,16 +57,13 @@ func (this *statsResults) checkSimilarDistribution(expected *statsResults) error func getStatsResults(samples []float64) *statsResults { res := new(statsResults) - var sum float64 - for i := range samples { - sum += samples[i] + var sum, squaresum float64 + for _, s := range samples { + sum += s + squaresum += s * s } res.mean = sum / float64(len(samples)) - var devsum float64 - for i := range samples { - devsum += math.Pow(samples[i]-res.mean, 2) - } - res.stddev = math.Sqrt(devsum / float64(len(samples))) + res.stddev = math.Sqrt(squaresum/float64(len(samples)) - res.mean*res.mean) return res } |