Problem with axis labels (line series with small values)

[dimitrig]

Hi,

I'm having the following problem (shown in the screenshot):



As you can see the bottom label of the left axis should be indicating 0, but instead a very small value is displayed (looks at first sight like some rounding problem of some sort).

You can replicate the problem very easily. Just add a TeeChart to your form and disable 3D. Then add a line series to it and make sure that the pointers of that line are visible. Set the ValueFormat of the Left Axis to "E6".
Then simply add a button to your form and insert the following event handler behind it:

Code: Select all

private void button1_Click(object sender, EventArgs e)
{
    Random rnd = new Random();
    line1.Clear();
    for (int pointIndex = 0; pointIndex < 25; pointIndex++)
    {
        line1.Add(rnd.NextDouble() * 10, rnd.NextDouble() * 256 / 1e6);
    }
}

Simply run the application. Every time the button will be clicked, new random data will be generated for the line. It will not take you many times, pressing this button, to replicate the problem I've shown in the screenshot. It sometimes depends on the size of the TeeChart/Form, so maybe you have to play a little bit with that as well.

I can only replicate this problem when the pointers are visible, it seems not to manifest itself when they are not visible. So I've got the impression that it has got something to do with that.

I'm using the latest stable build v2.0.2456.16162.

Regards

[Narcís]

Hi dimitrig,

I could reproduce the issue here and added it (TF02011789) to our defect list to be fixed for future releases.

[dimitrig]

Hi,

I'm using the latest version of the library (2.0.2586.24039), and this bug is still present (half year has passed since then). Any idea when this will be fixed and/or is it possible to speed up this fix, since it's important for us that this is solved?

Regards

[Narcís]

Hi dimitrig,

We have checked that this is not a bug as chart axis is resized to accommodate for pointer width/height. You can't have the scale at [0,..] and offset/show full pointers.

However you can set the Pointer.InflateMargins to false to have a chart display only [0,..], eg.:

Code: Select all

			line1.Pointer.InflateMargins = false;

[dimitrig]

Hi Narcís,

Thanks again for the quick reply. We're using a couple of other software packages, and I have to say that Steema's support is certainly the best I've ever encountered. For all the topics I've posted so far, I've always received a quick response, and that's a very comfortable feeling (knowing that support is there when you need it). Even if no solution or work-around is given, it's nice to know that somebody actually took the time to look in detail (no auto-response kind of thing) and respond to the topic. So I have to congratulate you for doing a very good job!


I'm not totally convinced that this is not a bug. You have to agree with me, that by just looking at the screenshot I've posted, this is a very unconventional way of displaying the bottom label. You're using an offset 2E-5 for each tick, and then suddenly, for internal reasons (since you're displaying the rectangles for the points), you decide to alter this offset.

The explanation about the pointers being the reason for this is also not totally valid, I think. The width of the pointer in the chart would easily take 2e-6 in value (just an estimation by looking at the chart). The zero line would be therefore located exactly on the same spot as it is now (not distinguishable at value in the range of e-20). So, I don't totally follow why the pointers are the reasons that this is happening. You're not doing it when the pointers are not visible, so why do it now (width of pointers is much bigger)?

I can't comment for other people, but I'm simply guessing that a lot of people would find this behavior very unconventional. At least in my company, everybody agrees with this statement.
It could be that I'm wrong and that certain people like to see it this way. We're active in the HF Engineering world, so maybe this is the default way to do it for other activities (financial, business, ...). Maybe other people can comment on this in this forum?

[Narcís]

Hi dimitrig,

Sorry but we thought you were complaining about bottom axis labeling here. That's the reason of pointer's answer.

Regarding left axis issue, we still consider a bug and hasn't been fixed for now.