extract data from a matrix

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Linden 2013-8-5

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Hi, My matrix contains 200 X variables and 20 Z variables. All of them are properly named with a string name, i.e., X1...X200,Z1...Z20. How can I extract Zs out by using the string names, i.e. don't use column numbers. Many thanks.

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David Sanchez 2013-8-5

How/Where are you storing the name strings? Are they in an independent cell array?

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Answer 1

Jan 2013-8-5

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Using "X1" to "X200" is a really bad idea, see FAQ: How to create A1, A2, ... in a loop. Such hiding of an index in a name of a variable demands for complicated methods for the creation and access without offering any benefit.

It is not clear how the variables are stored in your "matrix", because matrices cannot contain "names". Are you talking about a cell of structs? Please post a meaningful example in valid Matlab syntax. Please add the new information by editing the original question, where readers expect all required information, while neither adding a comment or pseudo-answer is useful.

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Linden 2013-8-5

Hi Jan, thanks for your help. Data is read in from an excel sheet with Xs and Zs as names. So I have a matrix containing both the name of variables and values (A), a matrix only containing string of names (B) and a matrix containing values (C). I know how to extract variables from C. Suppose Z is from column 201 to 220 in C, can we use variable names to extract Z, rather than use C(:,201:220). Many thanks.

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