feat: add xyObjectMinMaxValues function

Author: targos

src/__tests__/__snapshots__/index.test.ts.snap

@@ -125,6 +125,7 @@ exports[`test existence of exported functions 1`] = `
   "xyObjectJoinX",
   "xyObjectMaxXPoint",
   "xyObjectMaxYPoint",
+  "xyObjectMinMaxValues",
   "xyObjectMinXPoint",
   "xyObjectMinYPoint",
   "xyObjectSlotX",

src/x/xCheck.ts

@@ -2,14 +2,18 @@ import type { NumberArray } from 'cheminfo-types';
 import { isAnyArray } from 'is-any-array';
 
 export interface XCheckOptions {
-  /** minimum length */
+  /**
+   * Minimum length
+   * @default 1
+   */
   minLength?: number;
 }
 
 /**
- * Checks if input is of type array.
- * @param input - input
- * @param options
+ * Checks if the input is a non-empty array of numbers.
+ * Only checks the first element.
+ * @param input - Array to check.
+ * @param options - Additional checks.
  */
 export function xCheck(
   input?: NumberArray,

src/x/xMinMaxValues.ts

@@ -5,7 +5,7 @@ import { xCheck } from './xCheck';
 /**
  * Return min and max values of an array.
  * @param array - array of number
- * @returns - Object with 2 properties, min and max
+ * @returns - Object with 2 properties, min and max.
  */
 export function xMinMaxValues(array: NumberArray): {
   min: number;

src/xyObject/__tests__/xyObjectCheck.test.ts

@@ -12,4 +12,16 @@ test('xyObjectCheck', () => {
   expect(() => xyObjectCheck('a')).toThrow(
     'points must be an array of {x,y} objects',
   );
+  expect(
+    xyObjectCheck(
+      [
+        { x: 0, y: 1 },
+        { x: 2, y: 3 },
+      ],
+      { minLength: 2 },
+    ),
+  ).toBeUndefined();
+  expect(() => xyObjectCheck([{ x: 0, y: 1 }], { minLength: 2 })).toThrow(
+    'points must have a length of at least 2',
+  );
 });

src/xyObject/__tests__/xyObjectMinMaxValues.test.ts

@@ -0,0 +1,30 @@
+import { expect, test } from 'vitest';
+
+import { xyObjectMinMaxValues } from '../xyObjectMinMaxValues';
+
+test('one element', () => {
+  expect(xyObjectMinMaxValues([{ x: 1, y: 2 }])).toStrictEqual({
+    minX: 1,
+    maxX: 1,
+    minY: 2,
+    maxY: 2,
+  });
+});
+
+test('multiple elements', () => {
+  expect(
+    xyObjectMinMaxValues([
+      { x: 1, y: 2 },
+      { x: 5, y: 4 },
+      { x: 3, y: 6 },
+      { x: -2, y: -5 },
+      { x: 0, y: 0 },
+    ]),
+  ).toStrictEqual({ minX: -2, maxX: 5, minY: -5, maxY: 6 });
+});
+
+test('throws error if array is empty', () => {
+  expect(() => xyObjectMinMaxValues([])).toThrow(
+    'points must have a length of at least 1',
+  );
+});

src/xyObject/index.ts

@@ -3,6 +3,7 @@ export * from './xyObjectCheck';
 export * from './xyObjectJoinX';
 export * from './xyObjectMaxXPoint';
 export * from './xyObjectMaxYPoint';
+export * from './xyObjectMinMaxValues';
 export * from './xyObjectMinXPoint';
 export * from './xyObjectMinYPoint';
 export * from './xyObjectSlotX';

src/xyObject/xyObjectCheck.ts

@@ -1,10 +1,24 @@
 import type { Point } from '../types';
 
+export interface XYObjectCheckOptions {
+  /**
+   * Minimum length
+   * @default 0
+   */
+  minLength?: number;
+}
+
 /**
- * Throws an error in not an array of x,y objects.
+ * Throws an error if it's not an array of x,y objects.
+ * Only checks the first element.
  * @param points - List of points.
+ * @param options - Additional checks.
  */
-export function xyObjectCheck(points?: Point[]): asserts points is Point[] {
+export function xyObjectCheck(
+  points?: Point[],
+  options: XYObjectCheckOptions = {},
+): asserts points is Point[] {
+  const { minLength = 0 } = options;
   if (!Array.isArray(points)) {
     throw new Error('points must be an array of {x,y} objects');
   }
@@ -14,4 +28,7 @@ export function xyObjectCheck(points?: Point[]): asserts points is Point[] {
   ) {
     throw new Error('points must be an array of {x,y} objects');
   }
+  if (minLength && points.length < minLength) {
+    throw new Error(`points must have a length of at least ${minLength}`);
+  }
 }

src/xyObject/xyObjectMinMaxValues.ts

@@ -0,0 +1,31 @@
+import type { Point } from '../types';
+
+import { xyObjectCheck } from './xyObjectCheck';
+
+/**
+ * Returns all min and max values of an array of points.
+ * @param points - Array of points {x,y}.
+ * @returns - Object with the 4 extrema.
+ */
+export function xyObjectMinMaxValues(points: Point[]): {
+  minX: number;
+  maxX: number;
+  minY: number;
+  maxY: number;
+} {
+  xyObjectCheck(points, { minLength: 1 });
+
+  let minX = points[0].x;
+  let maxX = minX;
+  let minY = points[0].y;
+  let maxY = minY;
+
+  for (const point of points) {
+    if (point.x < minX) minX = point.x;
+    if (point.x > maxX) maxX = point.x;
+    if (point.y < minY) minY = point.y;
+    if (point.y > maxY) maxY = point.y;
+  }
+
+  return { minX, maxX, minY, maxY };
+}