fix [turf-centroid] fixes centroid calculation

packages/turf-center-of-mass/test/out/linestring.geojson

@@ -6,7 +6,7 @@
       "properties": {},
       "geometry": {
         "type": "Point",
-        "coordinates": [4.860076904296875, 45.75919915723537]
+        "coordinates": [4.8600768820512945, 45.75919915730767]
       }
     },
     {

packages/turf-centroid/index.ts

@@ -1,5 +1,11 @@
 import { Feature, GeoJsonProperties, Point } from "geojson";
-import { point, AllGeoJSON } from "@turf/helpers";
+import {
+  point,
+  degreesToRadians,
+  radiansToDegrees,
+  earthRadius,
+  AllGeoJSON,
+} from "@turf/helpers";
 import { coordEach } from "@turf/meta";
 
 /**
@@ -26,17 +32,41 @@ function centroid<P extends GeoJsonProperties = GeoJsonProperties>(
 ): Feature<Point, P> {
   let xSum = 0;
   let ySum = 0;
+  let zSum = 0;
   let len = 0;
   coordEach(
     geojson,
     function (coord) {
-      xSum += coord[0];
-      ySum += coord[1];
+      xSum +=
+        Math.cos(degreesToRadians(coord[0])) *
+        Math.cos(degreesToRadians(coord[1])) *
+        earthRadius;
+      ySum +=
+        Math.sin(degreesToRadians(coord[0])) *
+        Math.cos(degreesToRadians(coord[1])) *
+        earthRadius;
+      zSum += Math.sin(degreesToRadians(coord[1])) * earthRadius;
       len++;
     },
     true
   );
-  return point([xSum / len, ySum / len], options.properties);
+  return point(
+    [
+      radiansToDegrees(Math.atan2(ySum / len, xSum / len)),
+      radiansToDegrees(
+        Math.asin(
+          zSum /
+            len /
+            Math.sqrt(
+              Math.pow(xSum / len, 2) +
+                Math.pow(ySum / len, 2) +
+                Math.pow(zSum / len, 2)
+            )
+        )
+      ),
+    ],
+    options.properties
+  );
 }
 
 export { centroid };

packages/turf-centroid/package.json

@@ -52,6 +52,7 @@
     "test:types": "tsc --esModuleInterop --module node16 --moduleResolution node16 --noEmit --strict types.ts"
   },
   "devDependencies": {
+    "@turf/circle": "workspace:^",
     "@types/benchmark": "^2.1.5",
     "@types/tape": "^4.13.4",
     "benchmark": "^2.1.4",

packages/turf-centroid/test.ts

@@ -7,6 +7,7 @@ import { writeJsonFileSync } from "write-json-file";
 import { featureEach } from "@turf/meta";
 import { featureCollection, lineString } from "@turf/helpers";
 import { centroid } from "./index.js";
+import { circle } from "@turf/circle";
 
 const __dirname = path.dirname(fileURLToPath(import.meta.url));
 
@@ -43,6 +44,20 @@ test("centroid", (t) => {
   t.end();
 });
 
+test("centroid -- circle consistency", (t) => {
+  const circ = circle([4.832, 45.7578], 4000);
+  const center = centroid(circ);
+  t.true(
+    Math.abs(center.geometry.coordinates[0] - 4.832) < 0.0000001,
+    "lon equality"
+  );
+  t.true(
+    Math.abs(center.geometry.coordinates[1] - 45.7578) < 0.0000001,
+    "lat equality"
+  );
+  t.end();
+});
+
 test("centroid -- properties", (t) => {
   const line = lineString([
     [0, 0],

packages/turf-centroid/test/out/feature-collection.geojson

@@ -8,7 +8,7 @@
       },
       "geometry": {
         "type": "Point",
-        "coordinates": [4.8336222767829895, 45.76051644154402]
+        "coordinates": [4.833622276817487, 45.76051644217321]
       }
     },
     {

packages/turf-centroid/test/out/imbalanced-polygon.geojson

@@ -8,7 +8,7 @@
       },
       "geometry": {
         "type": "Point",
-        "coordinates": [4.851791984156558, 45.78143055383553]
+        "coordinates": [4.851791902704642, 45.78143064842905]
       }
     },
     {

packages/turf-centroid/test/out/linestring.geojson

@@ -8,7 +8,7 @@
       },
       "geometry": {
         "type": "Point",
-        "coordinates": [4.860076904296875, 45.75919915723537]
+        "coordinates": [4.8600768820512945, 45.75919915730767]
       }
     },
     {

packages/turf-centroid/test/out/point.geojson

@@ -8,7 +8,7 @@
       },
       "geometry": {
         "type": "Point",
-        "coordinates": [4.831961989402771, 45.75764678012361]
+        "coordinates": [4.83196198940277, 45.75764678012361]
       }
     },
     {

packages/turf-centroid/test/out/polygon.geojson

@@ -8,7 +8,7 @@
       },
       "geometry": {
         "type": "Point",
-        "coordinates": [4.841194152832031, 45.75807143030368]
+        "coordinates": [4.841194013099296, 45.758082963072354]
       }
     },
     {

packages/turf-distance-weight/test.ts

@@ -52,7 +52,7 @@ test("turf-distance-weight", (t) => {
     p: 2,
     alpha: 1,
   });
-  t.equal(result[0][1], 0.5987182558007202, "change p");
+  t.equal(result[0][1], 0.5987182558007197, "change p");
 
   // test alpha
   result = distanceWeight(columbusJson, {
@@ -70,7 +70,7 @@ test("turf-distance-weight", (t) => {
     alpha: 1,
     standardization: true,
   });
-  t.equal(result[0][1], 0.5311565480348293, "standardization 1");
+  t.equal(result[0][1], 0.531156548034828, "standardization 1");
 
   result = distanceWeight(columbusJson, {
     threshold: 1,
@@ -83,7 +83,7 @@ test("turf-distance-weight", (t) => {
 
   // test default
   result = distanceWeight(columbusJson);
-  t.equal(result[0][1], 1.6702346893742355, "default arguments");
+  t.equal(result[0][1], 1.670234689374237, "default arguments");
 
   t.end();
 });