finding nearest number in matrices

hi I have 2 matrices A and B.

A=[0 0.375 0.405 0.452 0.500 0.530 0.577 0.623 0.639 0.670 0.701 0.717 0.748 0.779]
B=0:01:end

I want to find nearest number of A to 0.1 and then to 0.2 and then to 0.3 and ...

in this case the nearest numbers to 0.1 and 0.2 is 0.but I want a program that find the nearest number to 0.1 and put that number away and then find the nearest number to 0.2 and so on.

can you help me?

[Jan]

What have you tried so far?

"B = 0:01:end" is no valid Matlab syntax. Please edit the question and replace it by what you really want.

Answer 1

[Image Analyst]

What's the purpose of B? What is "end"?

Anyway, using A, try this:

clc;
A=[0 0.375 0.405 0.452 0.500 0.530 0.577 0.623 0.639 0.670 0.701 0.717 0.748 0.779]
for k = 1 : length(A)
  [~, nearestIndex(k)] = min(abs(A - k/10));
end
% Display in command window:
nearestIndex

[sajad]

B is 2nd matrix and end is length of A. your answer is right.but there is 2 choices for 0.1. suppose:

A=[0 0.375 0.405 0.452 0.500 0.530 0.577 0.623 0.639 0.670 0.701 0.717 0.748 0.779]

B=[0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5]

the nearest for 0 is 0

the nearest for 0.1 is 0 but I choose 0 before and I should chose 0.375

the nearest for 0.2 is 0.375 but I choose 0.375 before and I should chose 0.405 and so on

[Image Analyst]

OK (would have been good to explain B in the beginning). You accepted it, so did you adapt it to work with B yet? If not, try this:

clc;
A=[0 0.375 0.405 0.452 0.500 0.530 0.577 0.623 0.639 0.670 0.701 0.717 0.748 0.779]
B=[0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5]
for k = 1 : length(B)
  [~, nearestIndex(k)] = min(abs(A - B(k)));
end
% Display in command window:
nearestIndex
AValues = A(nearestIndex)

A =
         0    0.3750    0.4050    0.4520    0.5000    0.5300    0.5770    0.6230    0.6390    0.6700    0.7010    0.7170    0.7480    0.7790
B =
         0    0.1000    0.2000    0.3000    0.4000    0.5000    0.6000    0.7000    0.8000    0.9000    1.0000    1.1000    1.2000    1.3000    1.4000    1.5000
nearestIndex =
     1     1     2     2     3     5     7    11    14    14    14    14    14    14    14    14
AValues =
         0         0    0.3750    0.3750    0.4050    0.5000    0.5770    0.7010    0.7790    0.7790    0.7790    0.7790    0.7790    0.7790    0.7790    0.7790

[sajad]

thank you so much.

I used unique function to omit repeated numbers.

clc;

A=[0 0.375 0.405 0.452 0.500 0.530 0.577 0.623 0.639 0.670 0.701 0.717 0.748 0.779];

for k = 1 : length(A)

  [~, nearestIndex(k)] = min(abs(A - k/10));

end

s=unique(nearestIndex);

If I want k to start from 0 there is error.

what should I do for this?

thanks

[Image Analyst]

k is an index. Indexes can't start from 0 since they have to be integers starting at 1. However you can make another variable that is just k-1 if you want.

But anyway, that code doesn't use B like my latest code, so it's not right anyway.

[sajad]

I used your first code.

thanks

Answer 2

[Jan]

A = [0 0.375 0.405 0.452 0.500 0.530 0.577 0.623 0.639 0.670 0.701 0.717 ...
     0.748 0.779]
B = 0:0.1:1;   % Did you menat this?!

[value, index] = min(abs(bsxfun(@minus, A, B')))

[sajad]

No. thanks but previous answer is the thing I want.

I explained the exact thing in comment

thanks again