geojson-groupby v1.0.0

geojson-groupby

Group GeoJSON features or FeatureCollection based on associated properties and merge geometries to multigeometries.

installation

npm install geojson-groupby

usage

var geoGroupBy = require('geojson-groupby')
var group = geoGroupBy(array, properties [, collect])

• array Array of JSON objects

• properties Array JSON properties' path like address.city or lookup object

  lookup

  {
    intervals: array of numbers
    ,property: string
    [,labels: array of string]
  }

  intervals Array of intervals. Like 10, 20, 30, 40, 50 group the data in four ranges, whereas lower bound is inclusive and upper bound is exclusive.

  peroperty Property path like price

  labels Array of interval labels like 'low', 'medium', 'high'

• collect Array of properties that need to be collected in array

examples

data set

var features = [
  {
    "id": 1, "geometry": {"type": "Point", "coordinates": [10, 10]},
    "properties": {"color": "blue","price": 150,"address": {"city": "New York"}}
  }, {
    "id": 2, "geometry": {"type": "Point", "coordinates": [20, 20]},
    "properties": {"color": "green","price": 200,"address": {"city": "London"}}
  }, {
    "id": 3, "geometry": {"type": "Point", "coordinates": [30, 30]},
    "properties": {"color": "red","price": 210,"address": {"city": "London"}}
  }, {
    "id": 4, "geometry": {"type": "Point", "coordinates": [40, 40]},
    "properties": {"color": "red","price": 280,"address": {"city": "New York"}}
  }, {
    "id": 5, "geometry": {"type": "Point", "coordinates": [50, 50]},
    "properties": {"color": "green","price": 300,"address": {"city": "New York"}}
  }, {
    "id": 6, "geometry": {"type": "Point", "coordinates": [60, 60]},
    "properties": {"color": "red","price": 360,"address": {"city": "Mumbai"}}
  }
]
```

##### group features and merge geometries to multigeometries
```javascript
geoGroupBy(features, ['properties.color'])
// output as
{blue: {geometry: {type: 'MultiPoint', coordinates: [[10, 10]]}},
  green: {geometry: {type: 'MultiPoint', coordinates: [[20, 20], [50, 50]]}},
  red:
   {geometry:
      {type: 'MultiPoint',
        coordinates: [[30, 30], [40, 40], [60, 60]]}}}
```
##### group features, merge geometries to multigeometries and collect ids
```javascript
geoGroupBy(features, ['properties.color'],['id'])
// output as
{blue:
   {id: [1],
     geometry: {type: 'MultiPoint', coordinates: [[10, 10]]}},
  green:
   {id: [2, 5],
     geometry: {type: 'MultiPoint', coordinates: [[20, 20], [50, 50]]}},
  red:
   {id: [3, 4, 6],
     geometry:
      {type: 'MultiPoint',
        coordinates: [[30, 30], [40, 40], [60, 60]]}}}

```

This package `geojson-groupby` is based on [json-groupby](https://github.com/gagan-bansal/json-groupby), so please also check different [examples](https://github.com/gagan-bansal/json-groupby#examples) on usage of json-groupby
  
## developing
Once you run
 
```npm isntall```

then for running test 

```npm run test```

to create build

```npm run build```

## license
This project is licensed under the terms of the MIT license.