Reading plots back from graphs

[aaronwalsh]

Is it possible to read a plot back from a graph ?

My aim is to avoid duplication of large arrays in memory.

I dynamically allocate a large amount of memory and acquire data into it.  The data is then plotted on a graph.  I have set the graph 'DataMode' to 'Retain' so the graph keeps a copy of the array which enables the user to zoom.

I would like to de-allocate the memory and then read the plotted data from the graph, filter it and plot on a 2nd graph.

Is this possible ?

Thanks in advance for any suggestions.

[RobertoBozzolo]

Yes, you can: you must save the plot handle with which you can query some plot attributes with GetPlotAttribute. The relevant attributes are ATTR_PLOT_XDATA and ATTR_PLOT_YDATA, which return arrays of data. With other attributes which I cannot remember now you can obtain the number of ponts and datatype for each array, so you can dynamically dimension your memory before retrieving measurements from the control.

[aaronwalsh]

Thanks Roberto.  I'll use that method.

[Guillaume Dargaud]

Can this work with strip charts...?
I have a hunch that it doesn't and I said I would have it working by today
after (mis)remembering this post... C:-(
--
Guillaume Dargaud
http://www.gdargaud.net/