Hi,
LabVIEW graphs and charts are powerful in their means of presenting data. Charts ideal for scrolling through real / continious data i.e. that which is streamed across the plotting area. Waveform graphs work with array data type and plot in the order y=f(x). In this the index value for each element in the array is usually used as values for the x axis. XY graphs allow you to plot data without the fixed point spacing introducing greater flexibility and allowing one to plot wonderful curves, XY graphs accept 2 dimentional arrays for each axis etc. The context help guide is very useful for checking out what you need to wire up.
Arrays are essentially a set of data of the same data type for example a list of numbers. If you have already calculated your values for each axis you can plot these corespondingly. If you are working with LV 7.0 express or higher, you can use the Read from LVM file express VI [one with a blue background] to read from excel assuming you have the data already populated in cells of your excel spreadsheet file. Its quite simple, perhaps you could attach the excel file and I would gladly see what i can come up with.
You can programmatically calculate your vaules on the block diagram using the many mathematical functions that are available or even with the formula node.
I hope this helps!
Kind Regards,
Kurt
