MATLAB: How to find the intersection point of two vector arrays

intersection

if true
v1=[ 0    4.4847    8.9694   13.4541   18.3872   22.8719   26.2803   30.0474   33.7248   39.1962   45.2056   50.3182   54.8029   58.9288   64.2207   67.8981   71.5756   75.3427   76.2397  80.7243   85.2090];
v2=[ 0    7.9977   15.9954   23.9931   32.7905   40.7882   46.8665   53.5845   60.1426   69.8998   80.6167   89.7341   97.7318  105.0896  114.5269  121.0850  127.6431  134.3612  135.9607 143.9584  151.9561];
P=[0   15.0749   36.1817   57.8917   85.3013  133.7687  200.3439  279.9894  347.5677  411.8628  466.7912  502.3464  517.2896  525.3360  527.1648  510.7629  472.0163  310.0224  256.2738   0       0];
plot(v1,P,v2,P)
end

Best Answer

>> f{1} = griddedInterpolant(v1,P);
f{2} = griddedInterpolant(v2,P);
fzero(@(x)f{1}(x)-f{2}(x),[eps v1(end)])
ans =
   72.6470
>>

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>> f(8480:8500)
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One simple and efficient solution is to remove those 'S' characters before using sscanf:

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This correctly returns all 4297 numbers in the string, and can be easily adapted (e.g. using regexprep to remove specific types of characters, e.g. if it is possible that other alphabetic characters might occur in the string).

The simplest and most efficient solution by far is this:

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Note that that is not a CSV file, because the fields are not separated by commas. Judging by the header and the two tabs per row, this is actually a tab-separated file, where the middle column consists of one long string of space-separated integers. This is easy to parse using textscan and then sscanf:

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