feat(formater): formatNumber with relevant digits

src/formatter.js

@@ -0,0 +1,43 @@
+// https://code.open-xchange.com/#contentPanel;a7550a02-aa41-45d9-9cad-7e1c920815f3;null;ui/apps/io.ox/office/tk/utils.js;content
+
+const MULTIPLIER = 7;
+
+function normalizeNumber(number) {
+  // special handling for zero
+  if (number === 0) {
+    return { mant: 0, exp: 1 };
+  }
+
+  let exp = Math.floor(Math.log(Math.abs(number)) / Math.LN10);
+  const e = 10 ** exp;
+  let mant = number / e;
+
+  // due to rounding errors, the absolute value of the mantissa may become less than 1
+  if (Math.abs(mant) < 1) {
+    mant /= Math.abs(mant);
+  }
+
+  // due to rounding errors, the mantissa may become +-10 instead +-1, e.g. for the number 1000
+  if (Math.abs(mant) >= 10) {
+    mant /= 10;
+    exp += 1;
+  }
+
+  for (let i = 0; i <= MULTIPLIER; i += 1) {
+    mant /= 10;
+    exp += 1;
+  }
+
+  return { mant, exp };
+}
+
+export default function formatNumber(nr, digits) {
+  const n = normalizeNumber(nr);
+  const p = digits || 4;
+  const rounder = 10 ** (p + MULTIPLIER);
+
+  const mant = Math.round(n.mant * rounder) / rounder;
+
+  const e = 10 ** n.exp;
+  return mant * e;
+}