Plotting a circle with coordinate in excel

[trustmeasfrnd]

i ve a circle with 18 nodes and i want to plot it in excel may be using chart.it can be done.
now suppose i plotted a circle of diameter 2m then i have 18 nodes equally divided on its perimeter.what if i want to reduce the circle diameter to 1.8m how to generate its coordinate any easy way to do this?

	A	B	C	D
1	node number	x	y	z
2	100	-1	3	0
3	101	-0.9397	3	-0.342
4	102	-0.766	3	-0.6428
5	103	-0.5	3	-0.866
6	104	-0.1736	3	-0.9848
7	105	0.1736	3	-0.9848
8	106	0.5	3	-0.866
9	107	0.766	3	-0.6428
10	108	0.9397	3	-0.342
11	109	1	3	0
12	110	0.9397	3	0.342
13	111	0.766	3	0.6428
14	112	0.5	3	0.866
15	113	0.1736	3	0.9848
16	114	-0.1736	3	0.9848
17	115	-0.5	3	0.866
18	116	-0.766	3	0.6428
19	117	-0.9397	3	0.342

<colgroup><col style="width: 25pxpx"><col><col><col><col></colgroup><thead>
</thead><tbody>
</tbody>

Sheet1​

thanks and regards,
abhisekh

 

[MickG]

Maybe, multiply "X" and "Z" by 0.9 !! and plot in Scatter plot.

 

[trustmeasfrnd]

Hi MickG,
i plotted it and it looks like circle but how to check whether it is correct or not i mean any ways to confirm that circle dia is reduced or not?
can you also tell how you come up with 0.9 value can it be generalised as formula.

thanks and regards,
abhisekh

 

[MickG]

Not sure how helpful this is , but:-
NB:- 0.9 = 1.8/2.0

Below is the chart after size reduction i.e. Multiply "X" and "Z" by 0.9
The Actual circle size is only relative to the chart scales.
If you Plot the original data you will see, relative to the scales it has changed.

Modified Data series:-
NB: Extra (x-y) values added at bottom of data to complete circle !!!!

-0.9	0
-0.84573	-0.3078
-0.6894	-0.57852
-0.45	-0.7794
-0.15624	-0.88632
0.15624	-0.88632
0.45	-0.7794
0.6894	-0.57852
0.84573	-0.3078
0.9	0
0.84573	0.3078
0.6894	0.57852
0.45	0.7794
0.15624	0.88632
-0.15624	0.88632
-0.45	0.7794
-0.6894	0.57852
-0.84573	0.3078
-0.9	0

<colgroup><col width="84" style="width: 63pt; mso-width-source: userset; mso-width-alt: 2986;"> <col width="126" style="width: 95pt; mso-width-source: userset; mso-width-alt: 4494;"> <tbody> </tbody>

 

[trustmeasfrnd]

Not sure how helpful this is , but:-
NB:- 0.9 = 1.8/2.0

Below is the chart after size reduction i.e. Multiply "X" and "Z" by 0.9
The Actual circle size is only relative to the chart scales.
If you Plot the original data you will see, relative to the scales it has changed.

Modified Data series:-
NB: Extra (x-y) values added at bottom of data to complete circle !!!!

-0.9	0
-0.84573	-0.3078
-0.6894	-0.57852
-0.45	-0.7794
-0.15624	-0.88632
0.15624	-0.88632
0.45	-0.7794
0.6894	-0.57852
0.84573	-0.3078
0.9	0
0.84573	0.3078
0.6894	0.57852
0.45	0.7794
0.15624	0.88632
-0.15624	0.88632
-0.45	0.7794
-0.6894	0.57852
-0.84573	0.3078
-0.9	0

<tbody>
</tbody>

thank you,
I checked it by plotting both in same chart which shows that diameter is changed and then i also calculated it for each points by calculating dia using extreme points which is basis for plotting circle (x1-x2)^2+(y1-y2)^2 = Dia^2.

perfect. how do you attache chart here? i m curious may be i don't know have to dig more.
thank you again
regards

 

[MickG]

You're welcome

Paste chart:-
There's probably better ways but, I assign the code below to the chart:-

Sub Chart1_Click()
Const strPath As String = "C:\Users\USER1\Desktop\cam.gif"
ActiveSheet.ChartObjects(Application.Caller).Chart.Export strPath
End Sub

This creates a file on the desktop , then I upload it to Box.com, where I open it, copy it and then paste back into Forum Page.