turf-average


turf average module

$3

Calculates the average value of a field for a set of Point|points within a set of Polygon|polygons.

$3

| parameter | type | description |
| ------------- | ------------------------------ | ----------------------------------------------------------------------- |
| polygons | FeatureCollection\.\ | polygons with values on which to average |
| points | FeatureCollection\.\ | points from which to calculate the average |
| field | String | the field in the points features from which to pull values to average |
| outputField | String | the field in polygons to put results of the averages |

$3

``js
var polygons = {
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {},
"geometry": {
"type": "Polygon",
"coordinates": [[
[10.666351, 59.890659],
[10.666351, 59.936784],
[10.762481, 59.936784],
[10.762481, 59.890659],
[10.666351, 59.890659]
]]
}
}, {
"type": "Feature",
"properties": {},
"geometry": {
"type": "Polygon",
"coordinates": [[
[10.764541, 59.889281],
[10.764541, 59.937128],
[10.866165, 59.937128],
[10.866165, 59.889281],
[10.764541, 59.889281]
]]
}
}
]
};
var points = {
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {
"population": 200
},
"geometry": {
"type": "Point",
"coordinates": [10.724029, 59.926807]
}
}, {
"type": "Feature",
"properties": {
"population": 600
},
"geometry": {
"type": "Point",
"coordinates": [10.715789, 59.904778]
}
}, {
"type": "Feature",
"properties": {
"population": 100
},
"geometry": {
"type": "Point",
"coordinates": [10.746002, 59.908566]
}
}, {
"type": "Feature",
"properties": {
"population": 200
},
"geometry": {
"type": "Point",
"coordinates": [10.806427, 59.908910]
}
}, {
"type": "Feature",
"properties": {
"population": 300
},
"geometry": {
"type": "Point",
"coordinates": [10.79544, 59.931624]
}
}
]
};

var averaged = turf.average(
polygons, points, 'population', 'pop_avg');

var resultFeatures = points.features.concat(
averaged.features);
var result = {
"type": "FeatureCollection",
"features": resultFeatures
};

//=result
`


Returns FeatureCollection., polygons with the value of outField set to the calculated averages

Installation

Requires nodejs.

`sh
$ npm install turf-average
`

Tests

`sh
$ npm test
``