Initial data commit

Task/Angles-geometric-normalization-and-conversion/JavaScript/angles-geometric-normalization-and-conversion.js

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+/*****************************************************************\
+| Expects an angle, an origin unit and a unit to convert to,      |
+| where in/out units are:                                         |
+| --------------------------------------------------------------- |
+| 'D'/'d' ..... degrees             'M'/'d' ..... mils            |                                          |
+| 'G'/'g' ..... gradians            'R'/'r' ..... radians         |
+| --------------------------------------------------------------- |
+| example: convert 150 degrees to radians:                        |
+| angleConv(150, 'd', 'r')                                        |
+\*****************************************************************/
+function angleConv(deg, inp, out) {
+  inp = inp.toLowerCase();
+  out = out.toLowerCase();
+  const D = 360,
+        G = 400,
+        M = 6400,
+        R = 2 * Math.PI;
+  // normalazation
+  let minus = (deg < 0);  // boolean
+  deg = Math.abs(deg);
+  switch (inp) {
+    case 'd': deg %= D; break;
+    case 'g': deg %= G; break;
+    case 'm': deg %= M; break;
+    case 'r': deg %= R;
+  }
+  // we use an internal conversion to Turns (full circle) here
+  let t;
+  switch (inp) {
+    case 'd': t = deg / D; break;
+    case 'g': t = deg / G; break;
+    case 'm': t = deg / M; break;
+    case 'r': t = deg / R;
+  }
+  // converting
+  switch (out) {
+    case 'd': t *= D; break;
+    case 'g': t *= G; break;
+    case 'm': t *= M; break;
+    case 'r': t *= R;
+  }
+  if (minus) return 0 - t;
+  return t;
+}
+
+// mass testing
+let nums  = [-2, -1, 0, 1, 2, 6.2831853, 16, 57.2957795, 359, 399, 6399, 1e6],
+    units = 'dgmr'.split(''),
+    x, y, z;
+for (x = 0; x < nums.length; x++) {
+  for (y = 0; y < units.length; y++) {
+    document.write(`
+      <p>
+        <b>${nums[x]}<sub>${units[y]}</sub></b><br>
+    `);
+    for (z = 0; z < units.length; z++)
+      document.write(`
+        = ${angleConv(nums[x], units[y], units[z])}<sub>${units[z]}</sub>
+      `);
+  }
+}