From f42cfbb82c641e3f3ecb364f02fadcc0dd01462e Mon Sep 17 00:00:00 2001
From: Tinkoff DWH <tinkoff.dwh@gmail.com>
Date: Mon, 13 Mar 2017 15:48:23 +0500
Subject: [PATCH] [ZEPPELIN-2252] discreteness of line charts

---
 .../visualization/builtins/visualization-linechart.js | 11 ++++++++++-
 .../visualization/builtins/visualization-nvd3chart.js |  9 +++++++--
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/zeppelin-web/src/app/visualization/builtins/visualization-linechart.js b/zeppelin-web/src/app/visualization/builtins/visualization-linechart.js
index 90db33fdb13..02a2114d7ec 100644
--- a/zeppelin-web/src/app/visualization/builtins/visualization-linechart.js
+++ b/zeppelin-web/src/app/visualization/builtins/visualization-linechart.js
@@ -70,7 +70,12 @@ export default class LinechartVisualization extends Nvd3ChartVisualization {
   configureChart(chart) {
     var self = this;
     chart.xAxis.tickFormat(function(d) {return self.xAxisTickFormat(d, self.xLabels);});
-    chart.yAxis.tickFormat(function(d) {return self.yAxisTickFormat(d, self.xLabels);});
+    chart.yAxis.tickFormat(function(d) {
+      if (d === undefined) {
+        return 'N/A';
+      }
+      return self.yAxisTickFormat(d, self.xLabels);
+    });
     chart.yAxis.axisLabelDistance(50);
     if (chart.useInteractiveGuideline) {   // lineWithFocusChart hasn't got useInteractiveGuideline
       chart.useInteractiveGuideline(true); // for better UX and performance issue. (https://github.com/novus/nvd3/issues/691)
@@ -111,4 +116,8 @@ export default class LinechartVisualization extends Nvd3ChartVisualization {
       }
     };
   };
+
+  defaultY() {
+    return undefined;
+  };
 }
diff --git a/zeppelin-web/src/app/visualization/builtins/visualization-nvd3chart.js b/zeppelin-web/src/app/visualization/builtins/visualization-nvd3chart.js
index 61de1d91aac..b0f569e26de 100644
--- a/zeppelin-web/src/app/visualization/builtins/visualization-nvd3chart.js
+++ b/zeppelin-web/src/app/visualization/builtins/visualization-nvd3chart.js
@@ -81,6 +81,10 @@ export default class Nvd3ChartVisualization extends Visualization {
     return s;
   };
 
+  defaultY() {
+    return 0;
+  };
+
   xAxisTickFormat(d, xLabels) {
     if (xLabels[d] && (isNaN(parseFloat(xLabels[d])) || !isFinite(xLabels[d]))) { // to handle string type xlabel
       return xLabels[d];
@@ -98,6 +102,7 @@ export default class Nvd3ChartVisualization extends Visualization {
 
   d3DataFromPivot(
     schema, rows, keys, groups, values, allowTextXAxis, fillMissingValues, multiBarChart) {
+    var self = this;
     // construct table data
     var d3g = [];
 
@@ -181,10 +186,10 @@ export default class Nvd3ChartVisualization extends Visualization {
         }
 
         var xVar = isNaN(rowValue) ? ((allowTextXAxis) ? rowValue : rowNameIndex[rowValue]) : parseFloat(rowValue);
-        var yVar = 0;
+        var yVar = self.defaultY();
         if (xVar === undefined) { xVar = colName; }
         if (value !== undefined) {
-          yVar = isNaN(value.value) ? 0 : parseFloat(value.value) / parseFloat(value.count);
+          yVar = isNaN(value.value) ? self.defaultY() : parseFloat(value.value) / parseFloat(value.count);
         }
         d3g[i].values.push({
           x: xVar,