Merge pull request #162 from VisActor/fix/log-ticks

fix: fix the bug of log-scale ticks
VisActor · Dec 28, 2023 · 1157094 · 1157094
2 parents 8aee54e + f935b50
commit 1157094
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Showing 3 changed files with 21 additions and 10 deletions.
diff --git a/common/changes/@visactor/vscale/fix-log-ticks_2023-12-28-08-48.json b/common/changes/@visactor/vscale/fix-log-ticks_2023-12-28-08-48.json
@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "comment": "fix: fix the bug of log-scale ticks\n\n",
+      "type": "none",
+      "packageName": "@visactor/vscale"
+    }
+  ],
+  "packageName": "@visactor/vscale",
+  "email": "dingling112@gmail.com"
+}
diff --git a/packages/vscale/__tests__/log.test.ts b/packages/vscale/__tests__/log.test.ts
@@ -155,7 +155,7 @@ it('log.nice() nices the domain, extending it to powers of ten', () => {
 
 it('log.nice() works on degenerate domains', () => {
   const x = new LogScale().domain([0, 0]).nice();
-  expect(x.domain()).toEqual([0, 0]);
+  expect(x.domain()).toEqual([1e-16, 1e-15]);
   x.domain([0.5, 0.5]).nice();
   expect(x.domain()).toEqual([0.1, 1]);
 });
@@ -164,7 +164,7 @@ it('log.nice() on a polylog domain only affects the extent', () => {
   const x = new LogScale().domain([1.1, 1.5, 10.9]).nice();
   expect(x.domain()).toEqual([1, 1.5, 11]);
   x.domain([-124, -1.5, -0]).nice();
-  expect(x.domain()).toEqual([-1000, -1.5, -0]);
+  expect(x.domain()).toEqual([-1000, -1.5, -1e-16]);
 });
 
 it('log.nice() works on large domains with large or small base', () => {
@@ -369,15 +369,15 @@ function round(x: number) {
 it('log scale dont throw error when domain contain 0', () => {
   const scale = new LogScale().domain([0, 1000]).range([0, 10000]);
 
-  expect(scale.scale(100)).toBeCloseTo(9333.333333333334);
+  expect(scale.scale(100)).toBeCloseTo(9463.909295551413);
   expect(scale.scale(0)).toBeCloseTo(0);
   expect(scale.scale(1000)).toBeCloseTo(10000);
   expect(scale.ticks(5)).toEqual([0, 1, 1000]);
 });
 
 it('log scale dont throw error when domain contain 0 and negative value', () => {
   const scale = new LogScale().domain([-1000, 0]).range([0, 10000]);
-  expect(scale.scale(-160)).toBeCloseTo(530.5866782293836);
+  expect(scale.scale(-160)).toBeCloseTo(426.6638791545382);
   expect(scale.scale(0)).toBeCloseTo(10000);
   expect(scale.scale(-1000)).toBeCloseTo(0);
   expect(scale.ticks(5)).toEqual([-1000, -1, -0]);

diff --git a/packages/vscale/src/log-scale.ts b/packages/vscale/src/log-scale.ts
@@ -13,13 +13,13 @@ function reflect(f: (x: number) => number) {
   return (x: number) => -f(-x);
 }
 
-function limitPositiveZero(min: number = 1e-12) {
+function limitPositiveZero(min: number = Number.EPSILON) {
   return (x: number) => {
     return Math.max(x, min);
   };
 }
 
-function limitNegativeZero(min: number = 1e-12) {
+function limitNegativeZero(min: number = Number.EPSILON) {
   return (x: number) => {
     return Math.min(x, -min);
   };
@@ -118,8 +118,8 @@ export class LogScale extends ContinuousScale {
 
   d3Ticks(count: number = 10) {
     const d = this.domain();
-    let u = d[0];
-    let v = d[d.length - 1];
+    let u = this._limit(d[0]);
+    let v = this._limit(d[d.length - 1]);
     const r = v < u;
 
     if (r) {
@@ -232,8 +232,8 @@ export class LogScale extends ContinuousScale {
 
     if (niceType) {
       const niceDomain = nice(originalDomain.slice(), {
-        floor: (x: number) => this._pows(Math.floor(this._logs(x))),
-        ceil: (x: number) => Math.ceil(x)
+        floor: (x: number) => this._pows(Math.floor(this._logs(this._limit(x)))),
+        ceil: (x: number) => (Math.abs(x) >= 1 ? Math.ceil(x) : this._pows(Math.ceil(this._logs(this._limit(x)))))
       });
 
       if (niceType === 'min') {