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Re: rectangular to polar coordinates
Posted:
Oct 24, 1999 1:50 AM



Hi Tom,
I'm guessing that you are doing this in GSP, and I've done a similar thing in Cabri. I did it in Cabri using a macro and you maybe could do it through a script.
You would need a reference segment from (0,0) to (1,0) which you would use to norm the xstep and the ystep of the segment you wanted the length of. Then construct the segments that are the xstep and the ystep, and fins their lengths in inches or cm, and find the length of the reference segment in the same units. Divide the x and ysteps by the reference length and use those values with pythagoras to calculate the length of the segment in axes' units. If you can put all of that into a script it will give you what you want  the length of a segment in axes' units.
The construction works in GSP and I have attached a sketch (the built in notation tends the clutter the screen a bit). I guess it depends on whether it can be scripted. Good luck.
Regards,
Jon Roberts
Tom De Vries wrote:
> I was trying to create a sketch that would display the rectangular > coordinates of a point and also the polar coordinates of a point. I > must be missing something here, but when I went to display the length > of a line, I found I couldn't express this in "x  y" coordinate > length. I .E. length relative to the coordinate grid. I can get > inches and cm and pixels, but i want the "length" . > > For example, if I have the point with coordinates (3,4) and I measure > the length from (0,0) to (3,4) I would like to get 5 units. > > How would I do this? > > Tom



