fix(ui): render table cell as number only for numbers

ui/src/dashboards/utils/tableGraph.ts

@@ -304,14 +304,15 @@ export const transformTableData = (
   - `parseFloat('02abc')` is 2
 
 */
-export const isNumerical = <T>(x: T | string): x is string =>
-  !isNaN(Number(x)) && !isNaN(parseFloat(x as string))
+export const isNumerical = (x: number | string): boolean =>
+  typeof x === 'number' || (!isNaN(Number(x)) && !isNaN(parseFloat(x)))
 
 export const formatNumericCell = (
-  cellData: string,
+  cellData: string | number,
   decimalPlaces: DecimalPlaces
 ) => {
-  const cellValue = parseFloat(cellData)
+  const cellValue =
+    typeof cellData === 'number' ? cellData : parseFloat(cellData)
 
   if (isTruncatedNumber(cellValue, decimalPlaces)) {
     return toFixed(cellValue, decimalPlaces)

ui/src/shared/components/TableGraph.tsx

@@ -14,7 +14,6 @@ import {fastReduce} from 'src/utils/fast'
 import {ErrorHandlingWith, DefaultError} from 'src/shared/decorators/errors'
 import {
   getDefaultTimeField,
-  isNumerical,
   formatNumericCell,
 } from 'src/dashboards/utils/tableGraph'
 
@@ -480,7 +479,7 @@ class TableGraph extends PureComponent<Props, State> {
       return _.defaultTo(fieldName, '').toString()
     }
 
-    if (isNumerical(cellData)) {
+    if (typeof cellData === 'number') {
       return formatNumericCell(cellData, decimalPlaces)
     }
 
@@ -540,7 +539,7 @@ class TableGraph extends PureComponent<Props, State> {
     const isFieldName = this.isVerticalTimeAxis ? isFirstRow : isFirstCol
     const isFixedCorner = isFirstRow && isFirstCol
 
-    const cellDataIsNumerical = isNumerical(cellData)
+    const cellDataIsNumerical = typeof cellData === 'number'
 
     let cellStyle: React.CSSProperties = style // tslint:disable-line
     if (