I have been working on an application using the Form Editor and have run
into some snags that perhaps the forum can help me with. My application is
to create a plot of an equation, the coefficients of which I can modify
using a scroll bar. I have run the labs on the Form Editor and gl2 commands
and read the chapter in JfC on graphics and have gone about as far as I can.
My script so far is attached. I started from the dice one in the lab.

 

Here are my questions:

 

1.                   How do I obtain values of a coefficient (e.g. a in this
case) from the position of the scrollbar? I thought that this had to do with
the x and y values of sysdata but I couldn't get this to work. It looked as
if sysdata was updating the position of the mouse not the scrollbar.

2.                   I had though that clicking the scrollbar would trigger
the plot. It only does the first time so my program flow is not working as I
thought it should. Can anyone see what I am doing wrong?

3.                   I am a bit challenged by the scaling. The plots use the
top left corner as 0 0 and pixels for each axis. I'd like to use the bottom
left corner as the origin. Any easy way to do this? Also, you will see that
I am plotting outside the plot area. I presume this again is scaling so I
need somewhat to equate pixels and axis better than I am doing.

4.                   Finally, how do you put a frame around the plot and add
legends, titles and the like? 

 

Any assistance on any of these questions would be much appreciated.

 

Thanks

 

Bob

 

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