I would often use Excel for making designs in Macromedia Freehand. For example to draw a parabola I would use Excel to get these x y coordinates:
-2.5 6.25
-2 4
-1.5 2.25
-1 1
-0.5 0.25
0 0
0.5 0.25
1 1
1.5 2.25
2 4
2.5 6.25
Then I would select points one at a time and assign them the numbers my spreadsheet gives me. A laborious and time consuming process.

I found I could copy and paste excel data into Adobe Illustrator's graph tool. But just like Excel, it's very hard to get proportional images with the AI graph tool. Enter coordinates along a circular path and the graph is an ellipse. As for manipulating line weight, color, etc. it seems AI is even more awkward and cumbersome than Excel.

I find I can manually enter coordinates in AI as I did for Freehand. But the image is upside down! It bothers me that positive AI numbers are below the x axis.

I successfully edited individual points in Inkscape. But just like Freehand, editing many points is time consuming and laborious. Does Inkscape have a way to import x y coordinate numbers from a spreadsheet?

If I could make Inkscape my vector graphics work horse, I'd be very happy. I'm angry at Adobe for killing Freehand.

Hi.

For doing this I would use Veusz - by; first export to CSV from excel - import the data into Veusz - create the graph - save as SVG - edit / add to it in Inkscape.
Link; http://home.gna.org/veusz/

Another option if you are into programming.;
Here you can save your graph as svg as well.
http://matplotlib.sourceforge.net/

Third option is to "hand-edit" the SVG file; viewtopic.php?f=5&t=12384

Good Luck
RGDS
Ragnar