correctly handle categoricals that are not strings (#1346)

client/src/components/categorical/occupancy.js

@@ -101,7 +101,7 @@ class Occupancy extends React.PureComponent {
     const groupBy = world.obsAnnotations.col(metadataField);
     const occupancyMap = world.obsAnnotations
       .col(colorAccessor)
-      .histogram(groupBy);
+      .histogramCategorical(groupBy);
 
     const occupancy = occupancyMap.get(category.categoryValues[categoryIndex]);
 
@@ -117,7 +117,7 @@ class Occupancy extends React.PureComponent {
 
       let currentOffset = 0;
       const dfColumn = world.obsAnnotations.col(colorAccessor);
-      const categoryValues = dfColumn.summarize().categories;
+      const categoryValues = dfColumn.summarizeCategorical().categories;
 
       let o;
       let scaledValue;

client/src/util/dataframe/dataframe.js

@@ -12,7 +12,7 @@ import {
   summarizeCategorical as _summarizeCategorical
 } from "./summarize";
 import {
-  histogramCategorical,
+  histogramCategorical as _histogramCategorical,
   hashCategorical,
   histogramContinuous,
   hashContinuous
@@ -260,16 +260,20 @@ class Dataframe {
     /*
     Create histogram bins for this column.  Memoized.
     */
+    const _memoHistoCat = memoize(_histogramCategorical, hashCategorical);
+    const histogramCategorical = by => _memoHistoCat(get, by);
+    let histogram = null;
     if (isTypedArray(column)) {
       const mFn = memoize(histogramContinuous, hashContinuous);
-      get.histogram = (bins, domain, by) => mFn(get, bins, domain, by);
+      histogram = (bins, domain, by) => mFn(get, bins, domain, by);
     } else {
-      const mFn = memoize(histogramCategorical, hashCategorical);
+      histogram = histogramCategorical;
-      get.histogram = by => mFn(get, by);
     }
 
     get.summarize = summarize;
     get.summarizeCategorical = summarizeCategorical;
+    get.histogram = histogram;
+    get.histogramCategorical = histogramCategorical;
     get.asArray = asArray;
     get.has = has;
     get.ihas = ihas;