Inverted logariphmic scale bug

[neurosoft]

Steema TeeChart Build 4.1.2010.11303

We have some problems with incorrect work of the TChart component in the case when left-axis is the logarithmic scale and inverted.

Here is a simple example of this error:
1. Create fastline series
2. Left-axis is a logarithmic scale and inverted.
3. Other parameters are default.
4. The values of the series are given by two arrays X and Y. (Method Series[0].Add(X,Y))
X = (0,2,4,6,8) Y = (6, 0.1, 4, 0, 4)

After added this series we have

error1.PNG (17.48 KiB) Viewed 5652 times

It is obvious that point (2;0.1) must be below the point (6;0) because 0.1> 0. It is bug.
After moving this graph (right mouse button is pressed), we get correct graph

error3.PNG (17.51 KiB) Viewed 5659 times

[Sandra]

Hello neurosoft,

Using next code:

Code: Select all

Steema.TeeChart.Styles.FastLine Series1;
   
        private void InitializeChart()
        {
            tChart1.Aspect.View3D = false;
            double [] X = new double[] {0.0,2.0,4.0,6.0,8.0}; 
            double [] Y = new double[] {6.0,0.1,4.0,0.0,4.0};
            Series1 = new Steema.TeeChart.Styles.FastLine(tChart1.Chart);
            Series1.Add(X, Y);
            tChart1.Axes.Left.Logarithmic = true;
            tChart1.Axes.Left.LogarithmicBase = 10;
            tChart1.Axes.Left.Inverted = true;
            tChart1.Axes.Left.AutomaticMinimum = false;
            tChart1.Axes.Left.Minimum = 0.005;
        }

I have achieved next image:

ChartLog.jpg (52.36 KiB) Viewed 5587 times

In image you can see that the points are drawn correctly, if you look for example at 0 it is painted above of 0.1 and as left axis is inverted it is correct. So in my opinion property of axes logarithmic, works fine for me. If you think that is not correct for you, please explain exactly why, so we can help you in this.

Thanks,

[neurosoft]

Dear Sandra, the example that you sent is really working. But then we apply true value to the parameter tChart1.Axes.Left.AutomaticMinimum the drawing becomes incorrect (Fig.1)

Fig1.PNG (26.24 KiB) Viewed 5543 times

You have to agree that it should work correctly with any value of this parameter. Besides when we scroll the chart up (dragging with right mouse button) the drawing also becomes incorrect (Fig. 2). Please test this more thoroughly.

Fig2.PNG (24.24 KiB) Viewed 5545 times

[Sandra]

Hello neurosoft,

I have added your request in bug list report with number [TF02015429]. We try to fix it for next maintenance releases of TeeChart.Net. On the other hand, I inform you that there is a new maintenance releases of TeeChart.Net in download page

Thanks,