calling a value in a matrix

I have two sets

X Y

1 2

3 6

4 7

5 8

I have to find highest value in category Y which is 8, after finding that 8 is the highest value I have to call value 5 in category X to from a matrix [ 5 8].

I know how to find the largest value, but I don’t know how to call 5 from X category.

Please can someone help me in call the specified value.

Answer 1

[galaxy]

Let 's try

X = [1 3 4 5];
Y = [2 6 7 8];
[max_val, idx] = max(Y);
X_idx = X(idx);

[sampath kumar punna]

Y

1 3

5 6

3 2

7 9

8 5

if Y is matrix , in the the second column we have values 2 and 5 , i want to call the row which is having value 2 and 5 in second column and from a new matrix

[ 3 2

8 5 ]

like this

[galaxy]

out = Y(find(Y(:,2) == 2 | Y(:,2) == 5 ), :);

Please accept my answer.

[sampath kumar punna]

Y = [1 7

3 9

11 12

15 18

22 12

12 23

15 19

10 22

17 28

111 123]

z= [ 9 12 18 12 23 19 22 28 123]

for i= 1: length(z)

out(i) = Y(find(Y(:,2) == z(:,i)))

end

this code shows some error can you fix this

[galaxy]

I can't believe that after I anwser for you, you accept your anwser.

I think you are unkind person. So I will not support you even it is very easy.

[sampath kumar punna]

im really sorry galaxy, i din't know that i have accepted my answer i thought i accepted your, i just saw my mistake and removed mine and accpected your. accepting my answer was not intentional, hope you understand.

[sampath kumar punna]

by any chance can you fix this error

Y = [1 7

3 9

11 12

15 18

22 12

12 23

15 19

10 22

17 28

111 123]

z= [ 9 12 18 12 23 19 22 28 123]

for i= 1: length(z)

out(i) = Y(find(Y(:,2) == z(:,i)))

end

this code shows an error while executing (Unable to perform assignment because the left and right sides have a different number of

elements.)

can anyone please fix this error

thanks

[galaxy]

Let 's try:

find_idx = find(Y(:,2) == z(1));
for i= 2: length(z)
    find_idx = vertcat(find_idx, find(Y(:,2) == z(i)));
end

out = Y(unique(find_idx), :);

you can try with other z:

example:

z= [ 9 12 18];

out =

3 9

11 12

15 18

22 12

Answer 2

[sampath kumar punna]

what if i have to call 7 from y and 4 from x