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In a matrix, there are some non-zero elements same as: aA=

enter image description here

Also, there is a list such as:

list = {a, b, c, d, e, f, g, ii, jj, kk};

I want to access to elements of the list which are not in the matrix. (I mean: 'c','d','g','jj') I use Complement to this work:

Complement[aA, list]

But Complement doesn't work.

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up vote 2 down vote accepted

Flatten the matrix first.

aA = {{a, b, 0}, {e, f, 0}, {ii, 0, kk}};
list = {a, b, c, d, e, f, g, ii, jj, kk};
Complement[list, Flatten@aA]

{c, d, g, jj}

share|improve this answer
I think for my goal, I must write: Complement[list, Flatten@aA] – Unbelievable Jun 3 '14 at 18:11
@mostafa Oh yes, I didn't read carefully. – mfvonh Jun 3 '14 at 18:14
thank you so much – Unbelievable Jun 3 '14 at 18:16

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