1 files changed, 8 insertions, 9 deletions
diff --git a/src/client/northstar/dash-fields/HistogramField.ts b/src/client/northstar/dash-fields/HistogramField.ts
index 90be70b80..82de51d56 100644
--- a/src/client/northstar/dash-fields/HistogramField.ts
+++ b/src/client/northstar/dash-fields/HistogramField.ts
@@ -16,7 +16,7 @@ export class HistogramField extends BasicField<HistogramOperation> {
     omitKeys(obj: any, keys: any) {
         var dup: any = {};
         for (var key in obj) {
-            if (keys.indexOf(key) == -1) {
+            if (keys.indexOf(key) === -1) {
                 dup[key] = obj[key];
             }
         }
@@ -27,7 +27,7 @@ export class HistogramField extends BasicField<HistogramOperation> {
     }
 
     Copy(): Field {
-        return new HistogramField(this.Data);
+        return new HistogramField(this.Data.Copy());
     }
 
     ToScriptString(): string {
@@ -35,13 +35,12 @@ export class HistogramField extends BasicField<HistogramOperation> {
     }
 
 
-    ToJson(): { type: Types, data: string, _id: string } {
+    ToJson() {
         return {
             type: Types.HistogramOp,
-
             data: this.toString(),
-            _id: this.Id
-        }
+            id: this.Id
+        };
     }
 
     @action
@@ -54,13 +53,13 @@ export class HistogramField extends BasicField<HistogramOperation> {
         let schema = CurrentUserUtils.GetNorthstarSchema(jp.SchemaName);
         if (schema) {
             CurrentUserUtils.GetAllNorthstarColumnAttributes(schema).map(attr => {
-                if (attr.displayName == jp.X.AttributeModel.Attribute.DisplayName) {
+                if (attr.displayName === jp.X.AttributeModel.Attribute.DisplayName) {
                     X = new AttributeTransformationModel(new ColumnAttributeModel(attr), jp.X.AggregateFunction);
                 }
-                if (attr.displayName == jp.Y.AttributeModel.Attribute.DisplayName) {
+                if (attr.displayName === jp.Y.AttributeModel.Attribute.DisplayName) {
                     Y = new AttributeTransformationModel(new ColumnAttributeModel(attr), jp.Y.AggregateFunction);
                 }
-                if (attr.displayName == jp.V.AttributeModel.Attribute.DisplayName) {
+                if (attr.displayName === jp.V.AttributeModel.Attribute.DisplayName) {
                     V = new AttributeTransformationModel(new ColumnAttributeModel(attr), jp.V.AggregateFunction);
                 }
             });