speed-percentile

A JavaScript utility to compute percentile speed from speed histogram.

Example:

var percentile = require('speed-percentile');

var histogram = {20: 1, 21: 1, 22: 2, 23: 3, 24: 4, 25: 5};

var speed = percentile(histogram, 0.85, 'R4');
//=> 24.52

Install

npm install speed-percentile

Test

cd to speed-percentile folder then run

npm test

Syntax

percentile

var o1 = percentile(P1, P2, P3)

Computes the p-th precentile speed from a sparse hash speed histogram.

Inputs:

| param | data type | description | |---|---|---| | P1 | associative array with integer keys | speed histogram hash {<speed>:<count>}| | P2 | number or array | one or more percentiles in decimal | | P3 | string | algorithm flag (optional): 'R4', 'R5' (default) |

Algorithms:

• R4 – R's sample quantile Type 4, but with linearly interpolated lower tail
• R5 – R's sample quantile Type 5, but with both tails linearly interpolated

Outputs:

| output | data type | description | |:--|:--|:--| | o1 | number or array | corresponding speed(s) sorted in descending order |