Merge pull request #1887 from plotly/histogram-mucho-bins-fix

Compute histogram bin positions beyond length 5000

Author: etpinard

src/traces/histogram/calc.js

@@ -106,7 +106,7 @@ module.exports = function calc(gd, trace) {
     // decrease end a little in case of rounding errors
     binend = pr2c(binspec.end) + (i - Axes.tickIncrement(i, binspec.size, false, calendar)) / 1e6;
 
-    while(i < binend && pos.length < 5000) {
+    while(i < binend && pos.length < 1e6) {
         i2 = Axes.tickIncrement(i, binspec.size, false, calendar);
         pos.push((i + i2) / 2);
         size.push(sizeinit);
@@ -116,6 +116,8 @@ module.exports = function calc(gd, trace) {
         // nonuniform bins also need nonuniform normalization factors
         if(densitynorm) inc.push(1 / (i2 - i));
         if(doavg) counts.push(0);
+        // break to avoid infinite loops
+        if(i2 <= i) break;
         i = i2;
     }
 

test/jasmine/tests/histogram_test.js

@@ -246,6 +246,19 @@ describe('Test histogram', function() {
             ]);
         });
 
+        it('should handle very small bins', function() {
+            var out = _calc({
+                x: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
+                xbins: {
+                    start: 0,
+                    end: 10,
+                    size: 0.001
+                }
+            });
+
+            expect(out.length).toEqual(9001);
+        });
+
         describe('cumulative distribution functions', function() {
             var base = {
                 x: [0, 5, 10, 15, 5, 10, 15, 10, 15, 15],