Custom Axis label format

[Angelo]

Hi everybody.


I am trying to work with axis labels and I would like to have the values formatted as scientific notation like as:

1.3x10-2 (-2 in superscript) instead of 1.3E-2.

Is there an easy way to do that ?

[Sandra]

Hello Angelo,

I recommend take a look to TeeChart Activex Demo project concretely to All Features\Axes\Labels\Exponent super-script. If you have any problem, please let me know.

I hope will helps.

Thanks,

[Angelo]

Hi Sandra. I checked that example and tried it, but it does not work accordingly.

Suppose I have the following data (X,Y)


(11,0.0005324)
(37,0.0007876)
(40,0.0010203)

if formatted as: "0.000E+0" the Y axis labels should be displayed as:

5.324x10(-4)
7.876x10(-4)
1.020x10(-3)

where (-4) and (-3) are the superscripts. The axis labels should be as written as above, but I it is not displayed because the format string "E-0" is not converted to "x10(-n)" where n is the superscript.

A "ugly" workaround for this I did setting the formatvalue="0.000x1OE-0" where I changed a "0" by "O" so I get:

5.324x1O(-4)
7.876x1O(-4)
1.020x1O(-3)

[Angelo]

Hi Sandra I just noticed that the problem also occurs with the demo !!!

See the legend and the vertical axis labels !

[Yeray]

Hi Angelo,

The following code seems to work fine for me here:

Code: Select all

Private Sub Form_Load()  
  TChart1.Aspect.View3D = False
  
  TChart1.AddSeries scPoint
  TChart1.Series(0).AddXY 11, 0.0005324, "", clTeeColor
  TChart1.Series(0).AddXY 37, 0.0007876, "", clTeeColor
  TChart1.Series(0).AddXY 40, 0.0010203, "", clTeeColor
  
  TChart1.Axis.Left.Labels.ValueFormat = "#.000 ""x10"" E+0"
  TChart1.Axis.Left.Labels.Exponent = True
End Sub

Private Sub TChart1_OnGetLegendText(ByVal LegendStyle As Long, ByVal ValueIndex As Long, LegendText As String)
  If LegendStyle = lsValues Then
    LegendText = Format$(TChart1.Series(0).YValues.Value(ValueIndex), "#.000 ""x10"" E+0")
  End If
End Sub

In TeeChart v2010 there is an AxisStyle named PointValue, only available at designtime for now. With it and the code above, the chart looks as follows:

Chart.png (7.78 KiB) Viewed 11749 times

In v7, the same code produces the following result:

Chart2.png (8.73 KiB) Viewed 11743 times

And zooming around the second point, it looks as follows:

Chart3.png (8.52 KiB) Viewed 11741 times

Isn't it what you are trying to achieve?