Add math

CHANGELOG.md

@@ -1,5 +1,11 @@
 # deverything
 
+## 0.27.0
+
+### Minor Changes
+
+- add math
+
 ## 0.26.0
 
 ### Minor Changes

README.md

@@ -30,6 +30,7 @@ Contributions always welcome!
   - `isPastDate()`
   - `isStringDate()` also checks if the string passed is a **valid** date
 - `isKey()` is a real key of an object
+- `isLastIndex()` is the index is the last item of array
 - `isNumber()` if the arg is number, and also usable (no infinity)
   - `isInt()`
   - `isEven()`
@@ -48,6 +49,13 @@ Contributions always welcome!
 - `isURL()`
 - `isUUID()`
 
+### Math
+
+- `average()`
+- `max()`
+- `min()`
+- `sum()`
+
 ### Helpers
 
 - `array()` create an arbitrary array based on a function

package.json

@@ -1,8 +1,8 @@
 {
   "name": "deverything",
-  "version": "0.26.0",
+  "version": "0.27.0",
   "description": "Everything you need for Dev",
-  "main": "dist/index.js",
+  "main": "./dist/index.js",
   "module": "./dist/index.mjs",
   "types": "./dist/index.d.ts",
   "sideEffects": false,

src/index.ts

@@ -1,5 +1,6 @@
 export * from "./checks";
 export * from "./helpers";
+export * from "./math";
 export * from "./random";
 export * from "./types";
 export * from "./validators";

src/math/average.test.ts

@@ -0,0 +1,13 @@
+import { describe, expect, test } from "@jest/globals";
+import { average } from "./average";
+
+describe("average", () => {
+  test("no arg", async () => {
+    expect(average([])).toBe(NaN);
+  });
+
+  test("args", async () => {
+    expect(average([1, 2])).toBe(1.5);
+    expect(average([1, 2, 3, 4])).toBe(2.5);
+  });
+});

src/math/average.ts

@@ -0,0 +1,10 @@
+/**
+ * Calculates the average of a list of numbers.
+ * @example
+ * average([1, 2, 3, 4, 5]); // 3
+ * average(1, 2, 3, 4, 5); // 3
+ */
+export const average = (numbers: number[]): number => {
+  const sum = numbers.reduce((total, num) => total + num, 0);
+  return sum / numbers.length;
+};

src/math/index.ts

@@ -0,0 +1,4 @@
+export * from "./average";
+export * from "./max";
+export * from "./min";
+export * from "./sum";

src/math/max.ts

@@ -0,0 +1,4 @@
+export const max = (values: number[]): number => {
+  const maxValue = Math.max(...values);
+  return maxValue;
+};

src/math/min.ts

@@ -0,0 +1,4 @@
+export const min = (values: number[]): number => {
+  const minValue = Math.min(...values);
+  return minValue;
+};

src/math/sum.test.ts

@@ -0,0 +1,28 @@
+import { describe, expect, test } from "@jest/globals";
+import { sum, sumBy } from "./sum";
+
+describe("sum", () => {
+  test("simple", async () => {
+    expect(sum([1, 2])).toBe(3);
+  });
+});
+
+describe("sumBy", () => {
+  test("simple", async () => {
+    expect(
+      sumBy([{ a: 1 }, { a: 2 }], (item) => {
+        return item.a;
+      })
+    ).toBe(3);
+  });
+  test("string", async () => {
+    expect(sumBy([{ a: 1 }, { a: 2 }], "a")).toBe(3);
+  });
+  test("complex", async () => {
+    expect(
+      sumBy([{ a: 1 }, { b: { a: 2 } }], (item) => {
+        return item.a || item.b?.a;
+      })
+    ).toBe(3);
+  });
+});

src/math/sum.ts

@@ -0,0 +1,13 @@
+import { PropertyAccessor, getProp } from "../_internals/getProp";
+import { PlainObject } from "../types";
+
+export const sum = (numbers: number[]) => {
+  return numbers.reduce((total, num) => total + num, 0);
+};
+
+export const sumBy = <T extends PlainObject>(
+  items: T[],
+  prop: PropertyAccessor<T>
+) => {
+  return items.reduce((total, item) => total + getProp<T>(item, prop), 0);
+};

src/validators/index.ts

@@ -8,6 +8,7 @@ export * from "./isFunction";
 export * from "./isFutureDate";
 export * from "./isJsDate";
 export * from "./isKey";
+export * from "./isLastIndex";
 export * from "./isNumber";
 export * from "./isNumeric";
 export * from "./isNumericId";

src/validators/isLastIndex.ts

@@ -0,0 +1,3 @@
+export const isLastIndex = (index: number, array: any[]) => {
+  return index === array.length - 1;
+};