Renumbering nodes in a pointcloud or matrix

Dear community,

I am trying to find a practical way to renumber the node IDs I get from my FEM software. As seen in the picture below, the node numbers are not in a perfect order.

My intention is to have a system with an increase of node numbers by coordinates.

That is,

N420 --> 1

N405 --> 2

N404 --> 3

N403 --> 4

N402 --> 5

N401 --> 6

N418 --> 7

N417 --> 8

...

Does anyone have a practical idea to sort/organize it?

Thank you very much.

The matrix here in this example is:

359	26.2702674865723	98.0414123535156	175
360	26.2703609466553	98.0413894653320	150.000015258789
361	26.2699527740479	98.0414962768555	124.999992370605
362	26.2697505950928	98.0415420532227	99.9999771118164
363	26.2697982788086	98.0415344238281	74.9999847412109
364	26.2699356079102	98.0414962768555	49.9999885559082
365	26.2700691223145	98.0414657592773	24.9999961853027
366	50.7500419616699	87.9015274047852	175
367	50.7501564025879	87.9014587402344	150.000015258789
368	50.7502784729004	87.9013824462891	125.000015258789
369	50.7503242492676	87.9013595581055	100.000022888184
370	50.7501449584961	87.9014663696289	75.0000076293945
371	50.7497825622559	87.9016876220703	49.9999885559082
372	50.7498664855957	87.9016342163086	24.9999923706055
373	71.7713394165039	71.7713394165039	175
374	71.7713394165039	71.7713394165039	150
375	71.7713394165039	71.7713394165039	125
376	71.7713394165039	71.7713394165039	100
377	71.7713394165039	71.7713394165039	75
378	71.7713394165039	71.7713394165039	50
379	71.7713394165039	71.7713394165039	25
380	87.9016342163086	50.7498664855957	175
381	87.9016876220703	50.7497825622559	150.000015258789
382	87.9014663696289	50.7501449584961	124.999992370605
383	87.9013595581055	50.7503242492676	99.9999771118164
384	87.9013824462891	50.7502784729004	74.9999847412109
385	87.9014587402344	50.7501564025879	49.9999885559082
386	87.9015274047852	50.7500419616699	24.9999980926514
387	98.0414657592773	26.2700691223145	175
388	98.0414962768555	26.2699356079102	150.000015258789
389	98.0415344238281	26.2697982788086	125.000015258789
390	98.0415420532227	26.2697505950928	100.000022888184
391	98.0414962768555	26.2699527740479	75.0000076293945
392	98.0413894653320	26.2703609466553	49.9999885559082
393	98.0414123535156	26.2702674865723	24.9999923706055
394	-6.21508222762180e-15	101.500000000000	25
395	-6.21508222762180e-15	101.500000000000	50
396	-6.21508222762180e-15	101.500000000000	75
397	-6.21508222762180e-15	101.500000000000	100
398	-6.21508222762180e-15	101.500000000000	125
399	-6.21508222762180e-15	101.500000000000	150
400	-6.21508222762180e-15	101.500000000000	175
401	26.2701263427734	98.0414505004883	0
402	50.7499885559082	87.9015579223633	0
403	71.7713394165039	71.7713394165039	0
404	87.9015579223633	50.7499885559082	0
405	98.0414505004883	26.2701263427734	0
406	26.2701263427734	98.0414505004883	200
407	50.7499885559082	87.9015579223633	200
408	71.7713394165039	71.7713394165039	200
409	87.9015579223633	50.7499885559082	200
410	98.0414505004883	26.2701263427734	200
411	101.500000000000	1.24301644552436e-14	175
412	101.500000000000	1.24301644552436e-14	150
413	101.500000000000	1.24301644552436e-14	125
414	101.500000000000	1.24301644552436e-14	100
415	101.500000000000	1.24301644552436e-14	75
416	101.500000000000	1.24301644552436e-14	50
417	101.500000000000	1.24301644552436e-14	25
418	-6.21508222762180e-15	101.500000000000	0
419	-6.21508222762180e-15	101.500000000000	200
420	101.500000000000	1.24301644552436e-14	0
421	101.500000000000	1.24301644552436e-14	200

[Rik]

Based on your previous question, I suspect you have tried something already. Did you manage to find the connected pairs?

[Deniz]

Ah yes, I switched to pointcloud and used [indices,dists] = findNearestNeighbors(ptCloud,dpoint,K); with N=5 neighbors(including itself).

Then within that small group, picked the ones I am interested by comparing their coordinates.

Now also managed to order them in terms of coordinates and then renumber the node IDs, but I am wondering if there is an easier way.