How to plot contours for a sparse data set?

[Geocentrix]

I am using the TContourPlot to show some data for which I have only 55 data points (data is inclued at the end of this post). On the plot below, I additionally draw small grey circles where my data points are located (i.e on a triangular pattern).

PileGroup.jpg (39.77 KiB) Viewed 210 times

The plot I am expecting to get is as follows:

Expected contours.jpg (50.12 KiB) Viewed 210 times

(I created this in Excel but had to interpolate between the data points, adding an extra point between every four circles)

However, I cannot get TChart to produce any contours for this data set.

Are there any settings within TChart that I can use to produce contours for this set?

Any suggestions would be most welcome!

Andrew

The data I have is as follows:

Code: Select all

Index	X	Y	Z
0	-8	192.4	0
1	8	192.4	0
2	2	195.3	-7
3	2	195.3	7
4	-2	195.3	-7
5	-2	195.3	7
6	-5	197.7	5.25
7	5	197.7	-5.25
8	5	197.7	5.25
9	-5	197.7	-5.25
10	7	200.4	1.75
11	-7	200.4	1.75
12	-7	200.4	-1.75
13	7	200.4	-1.75
14	-6	202.2	-3.5
15	6	202.2	-3.5
16	6	202.2	3.5
17	-6	202.2	3.5
18	-3	209.4	-5.25
19	3	209.4	5.25
20	-3	209.4	5.25
21	3	209.4	-5.25
22	-6	213.1	0
23	6	213.1	0
24	1	215	5.25
25	1	215	-5.25
26	-1	215	5.25
27	-1	215	-5.25
28	4	217.5	-3.5
29	4	217.5	3.5
30	-4	217.5	-3.5
31	-4	217.5	3.5
32	5	218.7	1.75
33	-5	218.7	-1.75
34	-5	218.7	1.75
35	5	218.7	-1.75
36	2	226.5	3.5
37	-2	226.5	-3.5
38	2	226.5	-3.5
39	-2	226.5	3.5
40	4	228.2	0
41	-4	228.2	0
42	0	229.4	3.5
43	0	229.4	-3.5
44	3	230.8	-1.75
45	-3	230.8	-1.75
46	3	230.8	1.75
47	-3	230.8	1.75
48	-1	236.8	1.75
49	1	236.8	1.75
50	1	236.8	-1.75
51	-1	236.8	-1.75
52	2	237.3	0
53	-2	237.3	0
54	0	240.3	0

The data used to produce the plot on Excel is:

Code: Select all

x	y	z
-8	189.6	0
-7	197.5	-1.75
-7	198.65	0
-7	197.5	1.75
-6	199.2	-3.5
-6	205.55	-1.75
-6	210	0
-6	205.55	1.75
-6	199.2	3.5
-5	194.8	-5.25
-5	205.95	-3.5
-5	215.5	-1.75
-5	216.475	0
-5	215.5	1.75
-5	205.95	3.5
-5	194.8	5.25
-4	205.1333333	-5.25
-4	214.3	-3.5
-4	220.525	-1.75
-4	224.9	0
-4	220.525	1.75
-4	214.3	3.5
-4	205.1333333	5.25
-3	206.3	-5.25
-3	217.8	-3.5
-3	227.4	-1.75
-3	228.375	0
-3	227.4	1.75
-3	217.8	3.5
-3	206.3	5.25
-2	192.4	-7
-2	208.45	-5.25
-2	223.2	-3.5
-2	229.45	-1.75
-2	233.8	0
-2	229.45	1.75
-2	223.2	3.5
-2	208.45	5.25
-2	192.4	7
-1	211.9	-5.25
-1	223.625	-3.5
-1	233.4	-1.75
-1	234.35	0
-1	233.4	1.75
-1	223.625	3.5
-1	211.9	5.25
0	216.6	-5.25
0	226	-3.5
0	232.4	-1.75
0	236.8	0
0	232.4	1.75
0	226	3.5
0	216.6	5.25
1	211.9	-5.25
1	223.625	-3.5
1	233.4	-1.75
1	234.35	0
1	233.4	1.75
1	223.625	3.5
1	211.9	5.25
2	192.4	-7
2	208.45	-5.25
2	223.2	-3.5
2	229.45	-1.75
2	233.8	0
2	229.45	1.75
2	223.2	3.5
2	208.45	5.25
2	192.4	7
3	206.3	-5.25
3	217.8	-3.5
3	227.4	-1.75
3	228.375	0
3	227.4	1.75
3	217.8	3.5
3	206.3	5.25
4	205.1333333	-5.25
4	214.3	-3.5
4	220.525	-1.75
4	224.9	0
4	220.525	1.75
4	214.3	3.5
4	205.1333333	5.25
5	194.8	-5.25
5	205.95	-3.5
5	215.5	-1.75
5	216.475	0
5	215.5	1.75
5	205.95	3.5
5	194.8	5.25
6	199.2	-3.5
6	205.55	-1.75
6	210	0
6	205.55	1.75
6	199.2	3.5
7	197.5	-1.75
7	198.65	0
7	197.5	1.75
8	189.6	0