[plt-scheme] request simple scheme code

Check out the FFI and the Plot collection. Open up Help Desk and type  
in plot or ffi in the search bar. The PLT Foreign Interface is what  
you want. -- Matthias




On Jan 23, 2007, at 6:03 PM, mikee wrote:

> Today I had an epiphany about something I have wanted to do for
> several years.  I know tcl/tk can do what I want, but they are slower
> than I want and I want to use scheme.  Will someone help me please
> with some starter code?
>
> What I want is for the plt-scheme program to call an external program
> that will generate some data.  I want this data plotted on a canvas
> (is that the right word?) as a line plot that if the plot is larger
> than the display window there are scroll bars (horizontal and
> vertical) to allow displaying of the plotted data.
>
> The application is a simple stock program to display a few custom
> values I am calculating in the external program. The sample scheme
> code would be great if it had some number (10?) of values in a list
> (or should it be an array?) and that list is handed to the plotting
> routine for display.
>
> The eventual application I have in mind a window that has a series of
> stock symbols vertically down the left side.  If the list is larger
> than the display window, the list scrolls.  These stock symbols are
> buttons and when clicked, the external program is called to retrieve
> the data, then the data is plotted on an adjacent window to the right
> for scrolling as necessary.
>
> Does that make sense?
>
> +------+---------------------+
> | SYM1 |           .     .   |
> |-SYM2-|          . .   .    |
> | SYM3 |         .   . .     |
> | SYM4 |    .   .     .      |
> | SYM4 |   . . .             |
> | SYM5 |  .   .              |
> | SYM7 | .                   |
> +------+---------------------+
>
> I realize this question(s) relates to more than constructing
> (define)'s and I appreciate any help given. I am looking to jump-start
> my efforts writing the above program. Seems like I need to download
> DrScheme to my iMac (aqua) for writing this. The C and perl, etc,
> is easy and mostly done.
>
> Mike
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