How to read a geojson file in javascript and get min or max of property?

Question

I'm new to js sorry if it's a stupid question. I guess there is two parts to my question.

What is the simplest way to read a geojson file with javascript ?

Right now I'm using :

var centrisData = $.getJSON( "Path to geojson");

My file looks something like that:

{
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "properties": {
        "type": "Maison\u00a0",
        "utilisation": "null",
        "piecesBeta": "20.0",
        "price": 3995000.0,
        "prixPiece_beta": 199750.0,
      },
    },
    {
      "type": "Feature",
      "properties": {
        "type": "Condo\u00a0",
        "utilisation": "null",
        "piecesBeta": "6.0",
        "price": 448900.0,
        "prixPiece_beta": 74816.67
      }
    }

I want to be able to get the min and max of the property "price". What would be the easiest way to do so ?

Thanks in advance !

Answer 1

You can loop over all of the features and keep and store the current minimum and maximum prices as variables.

const centrisData = {
  "type": "FeatureCollection",
  "features": [{
      "type": "Feature",
      "properties": {
        "type": "Maison\u00a0",
        "utilisation": "null",
        "piecesBeta": "20.0",
        "price": 3995000.0,
        "prixPiece_beta": 199750.0,
      },
    },
    {
      "type": "Feature",
      "properties": {
        "type": "Condo\u00a0",
        "utilisation": "null",
        "piecesBeta": "6.0",
        "price": 448900.0,
        "prixPiece_beta": 74816.67
      }
    }
  ]
};
let min = Infinity, max = -min;
for(const {properties: {price}} of centrisData.features){
  min = Math.min(min, price);
  max = Math.max(max, price);
}
console.log("Min:", min);
console.log("Max:", max);