[Lazarus] TAChart 2nd Y Axis

[David M. Lawrence]

The linear transform worked -- I finally figured out how to implement 
it. The chart is almost where it should be, except for the X-axis 
labels.  I need to dynamically define which of two options to use:

J F M A M J J A S O N D (MnthNHLabels) for northern hemisphere sites, and
J A S O N D J F M A M J (MnthSHLabels) for southern hemisphere sites.

The compiler seemed to have no problem with my code:

   if lat < 0 then ClimateDataChart.BottomAxis.Marks.Source := MnthSHLabels
     else ClimateDataChart.BottomAxis.Marks.Source := MnthNHLabels;

The data source options I have tried, however (TListChartSource and 
TUserDefinedChartSource) seem determined to convert the strings to 
numbers -- primarily 0.  What kind of chart source would allow me to use 
the strings above instead?  Or is there something else I would need to do?

Thanks again,

Dave

On 7/29/2011 1:45 AM, David M. Lawrence wrote:
>
> On 7/29/2011 1:21 AM, Alexander Klenin wrote:
>> I see now -- so you actually do NOT want auto-scale, but a fixed scale.
>> In this case, simply use linear transformation and then Chart.Extent 
>> property.
>>
>> You will have to calculate scale and offset yourself (once, at 
>> design-time).
>> (From my quick calculation, you should use scale=0.5 and offset=-90,
>> but check yourself)
> I'll check the linear transform.  Those values are what I was thinking 
> they should be.  I'll give them a shot.

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