[SOLVED] Graphing the equation for angle of trajectory using TCHART
lazarus / 55-TAChart

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sunbreezy393 · 2015-12-30 18:06

I am new to using Pascal/T Charts and was wandering how you would
graph the equation for the angle of trajectory?

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wp · 2015-12-30 18:13

http://wiki.lazarus.freepascal.org/TAChart_Tutorial:_Function_Series
is a tutorial with step-by-step instructions on how to plot functions
with TAChart.

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sunbreezy393 · 2015-12-30 18:18

Thanks for your help, but I have looked at this and it seems to work
if z and v are constants but not when they are variables.

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wp · 2015-12-30 18:28

So, you have a function of 2 variables, z = f(x,y)? You can use a
TColorMapSeries where one variable runs along the x and the other
variable along the y axis, and z is encoded as color shades. Have a
look at http://wiki.lazarus.freepascal.org/TAChart_Tutorial:_ColorMapS
eries,_Zooming.

But maybe I do not understand your question correctly. Can you post a
link or a sketch from which I could guess what the chart is supposed
to look like?

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sunbreezy393 · 2015-12-30 20:11

Here is an image of what the graph looks like

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wp · 2015-12-30 22:08

Not straightforward, probably too much for a beginner...

Paint the parabola by using the TFunctionSeries mentioned above, or a
standard TLineSeries
Then add an event handler to the OnAfterDraw event of the chart. Here
you select the points of further analysis where you calculate the
tangent vector, decompose it into its x and y components and paint the
corresponding lines and arrows. Find information on the OAfterDraw
painting in http://wiki.lazarus.freepascal.org/TAChart_Tutorial:_Backg
round_design.

Since this project looks like some homework assignment I do not want
to give more details, sorry.

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jmpessoa · 2015-12-31 00:20

Hello sunbreezy393!

maybe this component [and demos ]can help you:

https://github.com/jmpessoa/tfpmathexpressionbridge

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sunbreezy393 · 2016-01-01 23:51

Thank you very much for all your help, I have fixed the problem now.