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Topic: rectangular to polar coordinates
Replies: 2   Last Post: Oct 26, 1999 10:19 AM

 Messages: [ Previous | Next ]
 Jon Roberts Posts: 47 Registered: 12/6/04
Re: rectangular to polar coordinates
Posted: Oct 24, 1999 1:50 AM
 Axesunts.gsp (4.3 K)

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 x-step and the y-step of the segment you wanted the
length of. Then construct the segments that are the x-step and the
y-step, and fins their lengths in inches or cm, and find the length of
the reference segment in the same units. Divide the x- and y-steps 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

Date Subject Author
10/23/99 Tom De Vries
10/24/99 Jon Roberts
10/26/99 Nicholas Jackiw