turf-aggregate


turf aggregate module

$3

Calculates a series of aggregations for a set of Point|points within a set of Polygon|polygons. Sum, average, count, min, max, and deviation are supported.

$3

| parameter | type | description |
| -------------- | ------------------------------ | ------------------------------------------ |
| polygons | FeatureCollection\.\ | polygons with values on which to aggregate |
| points | FeatureCollection\.\ | points to be aggregated |
| aggregations | Array | an array of aggregation objects |

$3

``js
var polygons = {
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {},
"geometry": {
"type": "Polygon",
"coordinates": [[
[1.669921, 48.632908],
[1.669921, 49.382372],
[3.636474, 49.382372],
[3.636474, 48.632908],
[1.669921, 48.632908]
]]
}
}, {
"type": "Feature",
"properties": {},
"geometry": {
"type": "Polygon",
"coordinates": [[
[2.230224, 47.85003],
[2.230224, 48.611121],
[4.361572, 48.611121],
[4.361572, 47.85003],
[2.230224, 47.85003]
]]
}
}
]
};
var points = {
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {
"population": 200
},
"geometry": {
"type": "Point",
"coordinates": [2.054443,49.138596]
}
},
{
"type": "Feature",
"properties": {
"population": 600
},
"geometry": {
"type": "Point",
"coordinates": [3.065185,48.850258]
}
},
{
"type": "Feature",
"properties": {
"population": 100
},
"geometry": {
"type": "Point",
"coordinates": [2.329101,48.79239]
}
},
{
"type": "Feature",
"properties": {
"population": 200
},
"geometry": {
"type": "Point",
"coordinates": [2.614746,48.334343]
}
},
{
"type": "Feature",
"properties": {
"population": 300
},
"geometry": {
"type": "Point",
"coordinates": [3.416748,48.056053]
}
}
]
};
var aggregations = [
{
aggregation: 'sum',
inField: 'population',
outField: 'pop_sum'
},
{
aggregation: 'average',
inField: 'population',
outField: 'pop_avg'
},
{
aggregation: 'median',
inField: 'population',
outField: 'pop_median'
},
{
aggregation: 'min',
inField: 'population',
outField: 'pop_min'
},
{
aggregation: 'max',
inField: 'population',
outField: 'pop_max'
},
{
aggregation: 'deviation',
inField: 'population',
outField: 'pop_deviation'
},
{
aggregation: 'variance',
inField: 'population',
outField: 'pop_variance'
},
{
aggregation: 'count',
inField: '',
outField: 'point_count'
}
];

var aggregated = turf.aggregate(
polygons, points, aggregations);

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

//=result
`


Returns FeatureCollection., polygons with properties listed based on outField values in aggregations

Installation

Requires nodejs.

`sh
$ npm install turf-aggregate
`

Tests

`sh
$ npm test
``