Changed Computus in JavaScript, Typescript and added Computus in Dart

Author: hugo-s29

contents/computus/code/dart/gauss_easter.dart

@@ -0,0 +1,63 @@
+String computus(int year, {bool servois = false}) {
+  // Year's position in metonic cycle
+  final a = year % 19;
+
+  // Century index
+  final k = (year / 100).floor();
+
+  // Shift of metonic cycle, add a day offset every 300 years
+  final p = ((13 + 8 * k) / 25).floor();
+
+  // Correction for non-observed leap days
+  final q = (k / 4).floor();
+
+  // Correction to starting point of calculation each century
+  final M = (15 - p + k - q) % 30;
+
+  // Number of days from March 21st until the full moon
+  final d = (19 * a + M) % 30;
+
+  // Returning if user wants value for Servois' table
+  if (servois) {
+    return ((21 + d) % 31).toString();
+  }
+
+  // Finding the next Sunday
+  // Century-based offset in weekly calculation
+  final N = (4 + k - q) % 7;
+
+  // Correction for leap days
+  final b = year % 4;
+  final c = year % 7;
+
+  // Days from d to next Sunday
+  var e = (2 * b + 4 * c + 6 * d + N) % 7;
+
+  // Historical corrections for April 26 and 25
+  if (e == 6) {
+    if (d == 29 || (d == 28 && a > 10)) {
+      e = -1;
+    }
+  }
+
+  // Determination of the correct month for Easter
+  if (22 + d + e > 31) {
+    return 'April ${d + e - 9}';
+  } else {
+    return 'March ${22 + d + e}';
+  }
+}
+
+void main() {
+  print("The following are the dates of the Paschal full moon (using Servois " +
+      "notation) and the date of Easter for 2020-2030 AD:");
+
+  print("Year\tServois number\tEaster");
+
+  for (var year = 2020; year <= 2030; year++) {
+    final servoisNumber = computus(year, servois: true);
+    final easterDate = computus(year);
+
+    print('$year\t$servoisNumber\t\t$easterDate');
+  }
+}

contents/computus/code/javascript/gauss_easter.js

@@ -40,7 +40,9 @@ function computus(year, servois = false) {
   const d = (19 * a + M) % 30;
 
   // Returning if user wants value for Servois' table
-  if (servois) return ((21 + d) % 31).toString();
+  if (servois) {
+    return ((21 + d) % 31).toString();
+  }
 
   // Finding the next Sunday
   // Century-based offset in weekly calculation
@@ -54,11 +56,18 @@ function computus(year, servois = false) {
   let e = (2 * b + 4 * c + 6 * d + N) % 7;
 
   // Historical corrections for April 26 and 25
-  if (e === 6) if (d === 29 || (d === 28 && a > 10)) e = -1;
+  if (e === 6) {
+    if (d === 29 || (d === 28 && a > 10)) {
+      e = -1;
+    }
+  }
 
   // Determination of the correct month for Easter
-  if (22 + d + e > 31) return `April ${d + e - 9}`;
-  else return `March ${22 + d + e}`;
+  if (22 + d + e > 31) {
+    return `April ${d + e - 9}`;
+  } else {
+    return `March ${22 + d + e}`;
+  }
 }
 
 console.log(

contents/computus/code/typescript/gauss_easter.ts

@@ -6,49 +6,60 @@
  */
 
 function mod(a: number, b: number): number {
-  if (a < 0) return mod(a + b, b);
-  else return a % b;
+  if (a < 0) {
+    return mod(a + b, b);
+  } else {
+    return a % b;
+  }
 }
-
 function computus(year: number, servois: boolean = false): string {
   // Year's position in metonic cycle
-  const a = year % 19;
+  const a: number = year % 19;
 
   // Century index
-  const k = Math.floor(year / 100);
+  const k: number = Math.floor(year / 100);
 
   // Shift of metonic cycle, add a day offset every 300 years
-  const p = Math.floor((13 + 8 * k) / 25);
+  const p: number = Math.floor((13 + 8 * k) / 25);
 
   // Correction for non-observed leap days
-  const q = Math.floor(k / 4);
+  const q: number = Math.floor(k / 4);
 
   // Correction to starting point of calculation each century
-  const M = mod(15 - p + k - q, 30);
+  const M: number = mod(15 - p + k - q, 30);
 
   // Number of days from March 21st until the full moon
-  const d = (19 * a + M) % 30;
+  const d: number = (19 * a + M) % 30;
 
   // Returning if user wants value for Servois' table
-  if (servois) return ((21 + d) % 31).toString();
+  if (servois) {
+    return ((21 + d) % 31).toString();
+  }
 
   // Finding the next Sunday
   // Century-based offset in weekly calculation
-  const N = mod(4 + k - q, 7);
+  const N: number = mod(4 + k - q, 7);
 
   // Correction for leap days
-  const b = year % 4;
-  const c = year % 7;
+  const b: number = year % 4;
+  const c: number = year % 7;
 
   // Days from d to next Sunday
-  let e = (2 * b + 4 * c + 6 * d + N) % 7;
+  let e: number = (2 * b + 4 * c + 6 * d + N) % 7;
 
   // Historical corrections for April 26 and 25
-  if (e === 6) if (d === 29 || (d === 28 && a > 10)) e = -1;
+  if (e === 6) {
+    if (d === 29 || (d === 28 && a > 10)) {
+      e = -1;
+    }
+  }
 
   // Determination of the correct month for Easter
-  if (22 + d + e > 31) return `April ${d + e - 9}`;
-  else return `March ${22 + d + e}`;
+  if (22 + d + e > 31) {
+    return `April ${d + e - 9}`;
+  } else {
+    return `March ${22 + d + e}`;
+  }
 }
 
 console.log(
@@ -65,8 +76,8 @@ interface IOutputLine {
 const values: IOutputLine[] = [];
 
 for (let year = 2020; year <= 2030; year++) {
-  const servoisNumber = computus(year, true);
-  const easterDate = computus(year);
+  const servoisNumber: string = computus(year, true);
+  const easterDate: string = computus(year);
 
   // Creation of an object to be displayed as a line in the output table
   const line: IOutputLine = {

contents/computus/computus.md

@@ -320,10 +320,6 @@ For now, we have the code outputting a tuple of $$d$$ and $$e$$, so users can us
 [import, lang:"lisp"](code/clisp/gauss-easter.lisp)
 {% sample lang="nim" %}
 [import, lang:"nim"](code/nim/gauss_easter.nim)
-{% sample lang="javascript" %}
-[import, lang:"nim"](code/javascript/gauss_easter.js)
-{% sample lang="typescript" %}
-[import, lang:"nim"](code/typescript/gauss_easter.ts)
 {% endmethod %}