How to compare in matlab

Hi,

I have an array with 2*100 size. i want to check that a variable k with the 1st row of the array that k is equal or not to any value in the 1st row.

A=[3 4 6 3 5 4 2 56 7 7; 56 34 2 4 6 7 7 78];

variable k=3;

so i want to check k with A(1,1);A(1,2);A(1,3);......;A(1,n)

Answer 1

[Vieniava]

Try this:

TestA=( A(1,:) == k);

TestA is a logic vector or this

TestVec=find( A(1,:) == k);

TestVec - is a vector containg positions of matched values

[Sukumar Palo]

my array is of 201111111*2

in that how to find whether a 1 is returned or not in TestA.

[Vieniava]

use TestVec - TestVec would consist of indices of matched values ( A(1, TestVec) = k ).

Answer 2

[Sukumar Palo]

my array is of 2*201111111 in that how to find whether a 1 is returned or not in TestA.

[Oleg Komarov]

not clear at all...

Answer 3

[Walter Roberson]

ismember(k, TestA(1,:))

Answer 4

[Andreas Goser]

I suggest comparing the difference of A in k with a very small number:

f=abs(k-A(1,:))<2*eps

This avoids a couple of numerical surprises...

[Jan]

What about "2 * eps(k)" to consider k'th magnitude?

Answer 5

[Bo]

Any(A(1,:)==k)