New page for all concerts

software/backend/scripts/calcScripts.ts

@@ -0,0 +1,41 @@
+import { Rating } from "../models/acts/rating.model";
+
+/**
+ * Calculate the average of an Array of ratings
+ * 
+ * @param ratings Array of ratings
+ * 
+ * @returns Average rating as number
+ */
+export function calcOverallRating(ratings: Array<Rating>): number {
+  let sum = 0
+
+  for (let rating of ratings) {
+    sum += rating.dataValues.rating
+  }
+
+  return sum / ratings.length
+}
+
+/**
+ * Classifies a bunch of ratings to groups from 1 to 5 stars
+ * 
+ * @param ratings Array of RatingModels
+ * 
+ * @returns Array of Objects: { value: number[1-5], count: number }
+ */
+export function calcRatingValues(ratings: Array<Rating>) {
+  let ratingValues = [
+    { value: 1, count: 0 },
+    { value: 2, count: 0 },
+    { value: 3, count: 0 },
+    { value: 4, count: 0 },
+    { value: 5, count: 0 }
+  ]
+
+  for (let rating of ratings) {
+    ratingValues[rating.dataValues.rating - 1].count += 1
+  }
+
+  return ratingValues
+}