How can I equate all values of one vector to another and get the value ? Please find the example below
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If I have
dataA = [1,2,3,4,5,6,7,8,9];
dataB = [0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,1];
I need to equate for example: 1 = 0.1, 2=0.2, 3=0.3 so that if I ask value(7) it should display 0.7
Thank you in Advance.
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Rik
2019-2-18
If your data is already paired, what exactly do you want to do? Mathematically it doesn't really make sense to equate them, as they are not equal. What do you want to use this for? Maybe then we can help you solve that problem instead.
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Andrei Bobrov
2019-2-18
编辑:Andrei Bobrov
2019-2-18
dataA = [-496,-636,-52,175,-84,-248,-555,-423,34,-174]';
dataB = [-0.399609375000000,-0.512402343750000,-0.0418945312500000,...
0.140991210937500,-0.0676757812500000,-0.199804687500000,...
-0.447143554687500,-0.340795898437500,0.0273925781250000,-0.140185546875000]';
x = [-636,-84,34];
[lo,ii] = ismember(x,dataA);
out = dataB(ii(lo));
3 个评论
Stephen23
2019-2-18
编辑:Stephen23
2019-2-18
@madhan ravi: you are right, but only if all elements of x are members of dataA. Robust programming would not assume this, which is probably why Andrei Bobrov prefers ii(lo), thus allowing for non-member values without causing an error.
If a non-member value is unacceptable to the algorithm then it would still be better to use assert and write a specific error message, rather than just rely on the uninformative "Indices must be positive integers" that would occur otherwise.
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Jos (10584)
2019-2-18
You can use logical indexing, a very powerful tool in Matlab
tf = dataB == 7
dataA(tf)
4 个评论
Stephen23
2019-2-18
编辑:Image Analyst
2019-2-18
@Jos: I guess that should be with double equals:
dataB(dataA == -496)
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