[Fix] round the float number to up to 4 decimal places in table (#2163)

keplergl · Mar 25, 2023 · f640822 · f640822
1 parent a41e011
commit f640822
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Showing 3 changed files with 26 additions and 1 deletion.
diff --git a/src/utils/src/data-utils.ts b/src/utils/src/data-utils.ts
@@ -163,6 +163,14 @@ export function preciseRound(num: number, decimals: number): string {
   ).toFixed(decimals);
 }
 
+/**
+ * round a giving number at most 4 decimal places
+ * e.g. 10 -> 10, 1.12345 -> 1.2345, 2.0 -> 2
+ */
+export function roundToFour(num: number): number {
+  // @ts-expect-error
+  return Number(`${Math.round(`${num}e+4`)}e-4`);
+}
 /**
  * get number of decimals to round to for slider from step
  * @param step
@@ -258,6 +266,8 @@ export function roundValToStep(minValue: number, step: number, val: number): num
  */
 export const defaultFormatter: FieldFormatter = v => (notNullorUndefined(v) ? String(v) : '');
 
+export const floatFormatter = v => (isNumber(v) ? String(roundToFour(v)) : '');
+
 export const FIELD_DISPLAY_FORMAT: {
   [key: string]: FieldFormatter;
 } = {

diff --git a/src/utils/src/index.ts b/src/utils/src/index.ts
@@ -61,6 +61,7 @@ export {
   arrayMove,
   getFormatter,
   applyDefaultFormat,
+  roundToFour,
   getBooleanFormatter,
   applyCustomFormat,
   datetimeFormatter,

diff --git a/test/node/utils/data-utils-test.js b/test/node/utils/data-utils-test.js
@@ -30,7 +30,8 @@ import {
   arrayMove,
   getFormatter,
   defaultFormatter,
-  formatNumber
+  formatNumber,
+  roundToFour
 } from '@kepler.gl/utils';
 import {ALL_FIELD_TYPES} from '@kepler.gl/constants';
 
@@ -52,6 +53,19 @@ test('dataUtils -> preciseRound', t => {
   t.end();
 });
 
+test('dataUtils -> roundToFour', t => {
+  t.equal(roundToFour(1.2344), 1.2344, 'should round 1.2344 to 4 decimals correctly');
+  t.equal(roundToFour(13.23445), 13.2345, 'should round 13.23445 to 4 decimals correctly');
+  t.equal(roundToFour(13), 13, 'should round 13 to 4 decimals correctly');
+  t.equal(roundToFour(1.437), 1.437, 'should round 1.437 to 4 decimals correctly');
+  t.equal(
+    roundToFour(0.09999999999999987),
+    0.1,
+    'should round 0.09999999999999987 to 4 decimals correctly'
+  );
+  t.end();
+});
+
 test('dataUtils -> getRoundingDecimalFromStep', t => {
   t.equal(getRoundingDecimalFromStep(1), 0, 'decimal of step=int should be 0');
   t.equal(getRoundingDecimalFromStep(0.1), 1, 'decimal of step=0.1 should be 1');