how to add x^0 or y^0 variable in the function(dblquad)!!

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tony kevine 2015-4-20

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评论： Star Strider 2015-4-20

i have question about how to automatic add x^0 in a3 for every item.Because i must need dblquad.when i use the command without add x^0 by hand .it will error!!

but actually i have a lot of things like a3 without x variable or y variable so i need help.
What command can automatic add x or y variable.
a3=((2*y)/3 - 1)^2*(5085106975559725/144115188075855872 + 3243695640608965i/18446744073709551616)
b3=matlabFunction(a3)
c3=dblquad(b3,-1,1-1,1)% it will error beacuse no x^0 so any one have good ideal about it

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Answer 1

Star Strider 2015-4-20

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https://ww2.mathworks.cn/matlabcentral/answers/210442-how-to-add-x-0-or-y-0-variable-in-the-function-dblquad#answer_175864

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Your anonymous function ‘b3’ is a function of one variable. The MATLAB double integration functions want it to be a function of two variables. If you want to integrate it across ‘x’ as well, you would have to do something like this:

syms y x 
a3=((2*y)/3 - 1)^2*(5085106975559725/144115188075855872 + 3243695640608965i/18446744073709551616)
c3 = vpa(int(int(a3, y, -1, 1), x, -1, 1), 10)

produces: