How do I set a parameter based on individual values in an existing array? Should I use a for loop or something else?
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I need to have 'maxDistLine' be different for different 'L' values (i.e., if L<300, then maxDistLine should be 70, or else if L is between 300 and 1000 maxDistLine should be 50, else maxDistLine should be 20. I've tried using a 'for loop', 'while', and 'if/else' statements and nothing seems to work. Please see attached section of code. Thanks in advance for any help you could offer!
Section of Code:
C; %triplet center points
T; %triplet endpoints
Cgraph %The undirected graph of the center points
ArcPoints %2x4xN list of arc points CenterA-EndpointA-EndpointB-CenterB
C=fpep(:,7:8); %Central points
T=reshape( fpep(:,1:6) ,,2,3); %Triplet end-points Nx2x3
T=(T-C)./l2norm(T-C,2)*CTDist + C; %Normalize center to endpoint distances
DT=delaunayTriangulation(C); %Delaunay triangulation of centers
E=edges(DT); %Edge list
C1=C(E(:,1),:); %Center points listed for all DT edges
L=l2norm(C1-C2,2); %Center-to_center lengths for DT edges
the cyclist on 3 Jul 2022
My best guess here is that L is a vector, and you are expecting the if-else logic to work on the entire vector simultaneously. That's not how it works. For example
if L < 500
will only be true if all elements are less than 500. (The code won't check each element one-by-one.) This is described in the documentation for if, elseif, else.
So, you could loop over the elements, or you could vectorize explicitly, such as
maxDistLine = 21*(L<500) + 10*((L>=500)&(L<1000)) + 15*(L>1000)
dpb on 3 Jul 2022
The above if...elseif...else...end construct works; there are other ways -- one way w/ MATLAB is
using 1D lookup with builtin interp1. The eps() fixes up so the <= condition is met for the breakpoints.
An alternate that's a little more computationally efficient is a recast of the IF construct into a one-liner...
There are any number of ways to rewrite the above as well.
And, of course, the SWITCH construct could be used as well.
I'm sure others will think of many other similar implementations.