Reverted fix #13914, negative logarithmic axis.

highcharts · Aug 10, 2020 · 01b882e · 01b882e
1 parent 4584082
commit 01b882e
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Showing 5 changed files with 53 additions and 85 deletions.
diff --git a/js/Core/Axis/Axis.js b/js/Core/Axis/Axis.js
@@ -433,10 +433,7 @@ var Axis = /** @class */ (function () {
         // Placeholder for plotlines and plotbands groups
         axis.plotLinesAndBandsGroups = {};
         // Shorthand types
-        axis.positiveValuesOnly = !!(axis.logarithmic &&
-            !options.allowNegativeLog &&
-            !axis.allowNegativeLog // #13914 backwards compatibility
-        );
+        axis.positiveValuesOnly = !!axis.logarithmic;
         // Flag, if axis is linked to another axis
         axis.isLinked = defined(options.linkedTo);
         /**

diff --git a/js/Core/Axis/LogarithmicAxis.js b/js/Core/Axis/LogarithmicAxis.js
@@ -109,25 +109,9 @@ var LogarithmicAxisAdditions = /** @class */ (function () {
         return positions;
     };
     LogarithmicAxisAdditions.prototype.lin2log = function (num) {
-        if (this.axis.options.allowNegativeLog) {
-            var isNegative = num < 0;
-            num = Math.abs(num);
-            if (num < 1) {
-                return 0;
-            }
-            return (isNegative ? -1 : 1) * Math.pow(10, num);
-        }
         return Math.pow(10, num);
     };
     LogarithmicAxisAdditions.prototype.log2lin = function (num) {
-        if (this.axis.options.allowNegativeLog) {
-            var isNegative = num < 0;
-            num = Math.abs(num);
-            if (num < 1) {
-                return 0;
-            }
-            return (isNegative ? -1 : 1) * Math.log(num) / Math.LN10;
-        }
         return Math.log(num) / Math.LN10;
     };
     return LogarithmicAxisAdditions;
@@ -147,12 +131,8 @@ var LogarithmicAxis = /** @class */ (function () {
         // @todo Remove this in next major
         var axisProto = AxisClass.prototype;
         var logAxisProto = LogarithmicAxisAdditions.prototype;
-        axisProto.log2lin = function (num) {
-            return logAxisProto.log2lin.call({ axis: this }, num);
-        };
-        axisProto.lin2log = function (num) {
-            return logAxisProto.lin2log.call({ axis: this }, num);
-        };
+        axisProto.log2lin = logAxisProto.log2lin;
+        axisProto.lin2log = logAxisProto.lin2log;
         /* eslint-disable no-invalid-this */
         addEvent(AxisClass, 'init', function (e) {
             var axis = this;
@@ -194,14 +174,3 @@ var LogarithmicAxis = /** @class */ (function () {
 }());
 LogarithmicAxis.compose(Axis); // @todo move to factory functions
 export default LogarithmicAxis;
-/**
- * Activates rendering of negative logarithmic values.
- *
- * @sample highcharts/yaxis/type-log-negative
- *         Rendering negative logarithmic
- *
- * @type      {boolean}
- * @since     next
- * @apioption xAxis.allowNegativeLog
- */
-''; // keeps doclets above in transpiled file
diff --git a/samples/highcharts/yaxis/type-log-negative/demo.js b/samples/highcharts/yaxis/type-log-negative/demo.js
@@ -1,3 +1,45 @@
+/**
+ * Custom Axis extension to allow emulation of negative values on a logarithmic
+ * Y axis. Note that the scale is not mathematically correct, as a true
+ * logarithmic axis never reaches or crosses zero.
+ */
+(function (H) {
+    H.addEvent(H.Axis, 'afterInit', function () {
+        const logarithmic = this.logarithmic;
+
+        if (logarithmic && this.options.custom.allowNegativeLog) {
+
+            // Avoid errors on negative numbers on a log axis
+            this.positiveValuesOnly = false;
+
+            // Override the converter functions
+            logarithmic.log2lin = num => {
+                const isNegative = num < 0;
+
+                let adjustedNum = Math.abs(num);
+
+                if (adjustedNum < 10) {
+                    adjustedNum += (10 - adjustedNum) / 10;
+                }
+
+                const result = Math.log(adjustedNum) / Math.LN10;
+                return isNegative ? -result : result;
+            };
+
+            logarithmic.lin2log = num => {
+                const isNegative = num < 0;
+
+                let result = Math.pow(10, Math.abs(num));
+                if (result < 10) {
+                    result = (10 * (result - 1)) / (10 - 1);
+                }
+                return isNegative ? -result : result;
+            };
+        }
+    });
+}(Highcharts));
+
+
 Highcharts.chart('container', {
 
     title: {
@@ -11,11 +53,13 @@ Highcharts.chart('container', {
 
     yAxis: {
         type: 'logarithmic',
-        allowNegativeLog: true
+        custom: {
+            allowNegativeLog: true
+        }
     },
 
     series: [{
-        data: [-1000, -100, -10, -1, -0.1, 0, 0.1, 1, 10, 100, 1000, 10000]
+        data: [-1000, -100, -10, -1, -0.1, 0, 0.1, 1, 10, 100, 1000]
     }]
 
-});
+});
diff --git a/ts/Core/Axis/Axis.ts b/ts/Core/Axis/Axis.ts
@@ -4120,11 +4120,7 @@ class Axis implements AxisComposition, AxisLike {
         axis.plotLinesAndBandsGroups = {};
 
         // Shorthand types
-        axis.positiveValuesOnly = !!(
-            axis.logarithmic &&
-            !options.allowNegativeLog &&
-            !axis.allowNegativeLog // #13914 backwards compatibility
-        );
+        axis.positiveValuesOnly = !!axis.logarithmic;
 
         // Flag, if axis is linked to another axis
         axis.isLinked = defined(options.linkedTo);

diff --git a/ts/Core/Axis/LogarithmicAxis.ts b/ts/Core/Axis/LogarithmicAxis.ts
@@ -29,16 +29,11 @@ const {
 declare global {
     namespace Highcharts {
         interface Axis {
-            /** @deprecated */
-            allowNegativeLog?: boolean;
             /** @deprecated */
             lin2log(num: number): number;
             /** @deprecated */
             log2lin(num: number): number;
         }
-        interface XAxisOptions {
-            allowNegativeLog?: boolean;
-        }
     }
 }
 
@@ -209,26 +204,10 @@ class LogarithmicAxisAdditions {
     }
 
     public lin2log(num: number): number {
-        if (this.axis.options.allowNegativeLog) {
-            const isNegative = num < 0;
-            num = Math.abs(num);
-            if (num < 1) {
-                return 0;
-            }
-            return (isNegative ? -1 : 1) * Math.pow(10, num);
-        }
         return Math.pow(10, num);
     }
 
     public log2lin(num: number): number {
-        if (this.axis.options.allowNegativeLog) {
-            const isNegative = num < 0;
-            num = Math.abs(num);
-            if (num < 1) {
-                return 0;
-            }
-            return (isNegative ? -1 : 1) * Math.log(num) / Math.LN10;
-        }
         return Math.log(num) / Math.LN10;
     }
 
@@ -250,12 +229,8 @@ class LogarithmicAxis {
         // @todo Remove this in next major
         const axisProto = AxisClass.prototype;
         const logAxisProto = LogarithmicAxisAdditions.prototype;
-        axisProto.log2lin = function (num: number): number {
-            return logAxisProto.log2lin.call({ axis: this }, num);
-        };
-        axisProto.lin2log = function (num: number): number {
-            return logAxisProto.lin2log.call({ axis: this }, num);
-        };
+        axisProto.log2lin = logAxisProto.log2lin;
+        axisProto.lin2log = logAxisProto.lin2log;
 
         /* eslint-disable no-invalid-this */
 
@@ -307,16 +282,3 @@ interface LogarithmicAxis extends Axis {
 LogarithmicAxis.compose(Axis); // @todo move to factory functions
 
 export default LogarithmicAxis;
-
-/**
- * Activates rendering of negative logarithmic values.
- *
- * @sample highcharts/yaxis/type-log-negative
- *         Rendering negative logarithmic
- *
- * @type      {boolean}
- * @since     next
- * @apioption xAxis.allowNegativeLog
- */
-
-''; // keeps doclets above in transpiled file