dimension.multiselect boolean attr

Author: alexcjohnson

src/traces/parcoords/attributes.js

@@ -43,6 +43,8 @@ module.exports = {
             editType: 'calc',
             description: 'The shown name of the dimension.'
         },
+        // TODO: better way to determine ordinal vs continuous axes,
+        // so users can use tickvals/ticktext with a continuous axis.
         tickvals: extendFlat({}, axesAttrs.tickvals, {editType: 'calc'}),
         ticktext: extendFlat({}, axesAttrs.ticktext, {editType: 'calc'}),
         tickformat: {
@@ -103,6 +105,13 @@ module.exports = {
                 'of `[fromValue, toValue]` with finite numbers as elements.'
             ].join(' ')
         },
+        multiselect: {
+            valType: 'boolean',
+            dflt: true,
+            role: 'info',
+            editType: 'calc',
+            description: 'Do we allow multiple selection ranges or just a single range?'
+        },
         values: {
             valType: 'data_array',
             role: 'info',

src/traces/parcoords/axisbrush.js

@@ -271,7 +271,8 @@ function attachDragBehavior(selection) {
                 s.grabPoint = d.unitScaleInOrder(unitLocation) - pixelRange[0] - c.verticalPadding;
                 s.barLength = pixelRange[1] - pixelRange[0];
                 s.grabbingBar = active && intData.m && unitRange;
-                s.stayingIntervals = barInteraction
+                s.stayingIntervals = !d.multiselect ? [] :
+                    barInteraction
                     ? b.filter.get().filter(differentInterval(unitRange))
                     : b.filter.get(); // keep all preexisting bars if interaction wasn't a barInteraction
                 var grabbingBarNorth = intData.n;

src/traces/parcoords/defaults.js

@@ -60,6 +60,8 @@ function dimensionsDefaults(traceIn, traceOut) {
             coerce('ticktext');
             coerce('tickformat');
             coerce('range');
+
+            coerce('multiselect');
             coerce('constraintrange');
 
             commonLength = Math.min(commonLength, dimensionOut.values.length);

src/traces/parcoords/parcoords.js

@@ -224,6 +224,7 @@ function viewModel(state, callbacks, model) {
             tickvals: dimension.tickvals,
             ticktext: dimension.ticktext,
             ordinal: !!dimension.tickvals,
+            multiselect: dimension.multiselect,
             xIndex: i,
             crossfilterDimensionIndex: i,
             visibleIndex: dimension._index,