AddNullXY

[nefis]

Hello,

how can i add a invisible point to series wich not affect scale of the chart?
I mean when i use something like

TChart1.Series(0).AddNullXY(Now, 0, "")

the chart is rescaled to accomodate the new 0 value. Since the visible values are in range, say, 1000-1200 the chart becomes indecipherable

nefis

[Pep]

You could use the AddNull method :

TChart1.Series(0).AddNull ""

Josep Lluis Jorge
http://support.steema.com

[nefis]

You could use the AddNull method :

TChart1.Series(0).AddNull ""

Josep Lluis Jorge
http://support.steema.com

it's not working. you coud try it by corresponding modification of the "Multiple Axes" project from TeeChart samples

[SS]

To get around this we did two things.
1) if no non-null points previously in the series, once you have a good first point go back and update the value.

2) if other the previous value was not null then carry that value to the next null.

[Ex. if points 1 to 5 were value = 50 and point 6 is null then the value for point 6 use 50

-OR-
If points 1 to 5 were null and point 6 is value = 50 , go back and update points 1 to 5 to have a null value of 50]

[nefis]

To get around this we did two things.
1) if no non-null points previously in the series, once you have a good first point go back and update the value.

2) if other the previous value was not null then carry that value to the next null.

thanks, SS, it should work.
but I still hoping that there is a "normal" way to do it

nefis

[nefis]

Pep,

i'm still hoping that there is a "normal" way to do it. Is there?
The problem with the solution offered by SS is that there is a possibility of situation when long sequence of NULL values in a series happens in the very beginning of the series. It spoils output of series with "regular" values showed with the same axis.

nefis

[Christopher]

Hi -

i'm still hoping that there is a "normal" way to do it. Is there?

Mmm, well, neither AddNull() nor AddNullXY() offer the possibility of adding in a series point whose YValue is not associated with an axis.

The problem with the solution offered by SS is that there is a possibility of situation when long sequence of NULL values in a series happens in the very beginning of the series. It spoils output of series with "regular" values showed with the same axis.

OK. In this instance you will simply have to clear the series of all values and add in the Null values' YValue based on the data point YValue, no?

[nefis]

OK. In this instance you will simply have to clear the series of all values and add in the Null values' YValue based on the data point YValue, no?

I could think of ways around the issue. But the most simple solution might be NOT USING NULL POINTS IN MAX/MIN CALCULATIONS. the only problem with the solution is how to separate "regular" values fom Nulls. Well, you could use say minimal or maximal value for double type ( 4.94065645841247E-324 or 1.79769313486231E+308) as value of Null constant

nefis