How do I make this 2 dimensional vector follow a formula

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Jesse Crotts 2017-1-16

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评论： Jesse Crotts 2017-1-16

I want elements in a 2 dimensional vector two to follow a formula given its location (x,y) in the vector. For example, I want the formula to be like: "element" = 6xy+x+1. So if I looked at the 3rd position across and the 2 element down then it would say 40 because 6(3)(2)+3+1=40. I know that I can do this using 2 for loops but I was hoping for a more efficient way to do it.

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Answer 1

David Goodmanson 2017-1-16

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编辑：David Goodmanson 2017-1-16

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Hello Jesse, The standard way to do this is with the meshgrid function:

 x = 1:10;  % or whatever size it is
 y = 1:10;  % same comment
 [xx yy] = meshgrid(x,y);
 z = 6*xx.*yy+xx+1;

You have to use .* (dot multiply) in the appropriate places so the multiplication is term-by-term. In your case it looks like you want the x and y vectors to just be consecutive integers but in general x and y could have any values and do not even have to be sorted.