turf-deviation


turf deviation module

$3

Calculates the standard deviation value of a field for points within a set of polygons.

$3

| parameter | type | description |
| ---------- | ----------------- | -------------------------------------------------------- |
| polygons | FeatureCollection | a FeatureCollection of Polygon features |
| points | FeatureCollection | a FeatureCollection of Point features |
| inField | String | the field in points from which to aggregate |
| outField | String | the field to append to polygons representing deviation |

$3

``js
var polygons = turf.featurecollection([
turf.polygon([[
[-97.807159, 30.270335],
[-97.807159, 30.369913],
[-97.612838, 30.369913],
[-97.612838, 30.270335],
[-97.807159, 30.270335]
]]),
turf.polygon([[
[-97.825698, 30.175405],
[-97.825698, 30.264404],
[-97.630691, 30.264404],
[-97.630691, 30.175405],
[-97.825698, 30.175405]
]])
]);
var points = turf.featurecollection([
turf.point([-97.709655, 30.311245],
{population: 500}),
turf.point([-97.766647, 30.345028],
{population: 400}),
turf.point([-97.765274, 30.294646],
{population: 600}),
turf.point([-97.753601, 30.216355],
{population: 500}),
turf.point([-97.667083, 30.208047],
{population: 200})
]);

var inField = 'population';
var outField = 'pop_deviation';

var deviated = turf.deviation(
polygons, points, inField, outField);

var result = turf.featurecollection(
points.features.concat(deviated.features));

//=result
`

Installation

Requires nodejs.

`sh
$ npm install turf-deviation
`

Tests

`sh
$ npm test
``