Insert first element into existing column vector...

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David Pesetsky 2018-6-13

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回答： alfiya riyas 2019-12-26

采纳的回答： KSSV

Hello,

I am trying to just insert a 0 into my 48x1 double vector z, like this:

array = [0.0,z]

I keep getting:

Error using horzcat Dimensions of matrices being concatenated are not consistent.

What am I missing?

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Stephen23 2018-6-13

@David Pesetsky: What shape do you expect the output to be, when you concatenate these together horizontally: [1x1,48x1]. The first has one row, the second has 48 rows... how many rows should the output have? How many columns?

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Answer 1

KSSV 2018-6-13

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在 MATLAB Online 中打开

You should join them by using vertcat. Note that your z is row matrix.

z = rand(48,1) ;
array = [0.0 ;z]    % method 1
array = vertcat(0,z)  % or use vertcat

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David Pesetsky 2018-6-13

I used the:

array = [0.0 ;z]

method. I never saw a semicolon used like that. I had a space, and a comma. Both failed.

Stephen23 2018-6-13

@David Pesetsky: how to define matrices is explained in the introductory tutorials:

https://www.mathworks.com/help/matlab/getting-started-with-matlab.html

These explain many basic concepts that are invaluable for using MATLAB.

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Answer 2

alfiya riyas 2019-12-26

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In a column contains char vaues 'F' and 'M'.

i want to add values again 1 0 -1 in the same column using for loop

no of rows 6106 an the column no is 2

how to add these numbers usinf for ands if loop

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