Double integral error Matrix dimensions must agree
显示 更早的评论
I have a problem with computing a double integral. My code so far is:
B = 5;
L0 = 0:10;
A0 = 0:10;
tau = 1:100;
% Open and read the file
fid = fopen('first.txt', 'r');
data = cell2mat(textscan(fid, '%d'));
data = dlmread('first.txt');
% Two columns in the file
% First corresponds to time
t = data(:,1);
% Second to data values for luminosity
d = data(:,2);
% Posteriors for the three models 0,1&2
p0 = ((1./sqrt(2.*pi))^10).*(exp(-sum(0.5.*(d-B).^2)));
p1 =@(L0)((1./sqrt(2.*pi))^10).*(exp(-sum(0.5.*(d-B-L0).^2)));
p2 = @(A0,tau)((1./sqrt(2.*pi))^10).*(exp(-sum(0.5.*(d-B-A0.*exp(-t/tau)).^2)));
I1 = integral (p1, 0,10);
I2 = integral2 (p2,0, 10, 1, 100);
fclose(fid);
It seems to work fine for the normal integral I1 but crashes for the double integral I2. Any suggestions? ps. Sorry for the long equations
In the file, I have this:
0 7.108842
1 5.360705
2 5.871565
3 4.441087
4 6.877640
5 6.049399
6 5.587317
7 6.687828
8 7.390521
9 5.646180
2 个评论
Daniel kiracofe
2016-11-13
Suggest that you post the actual error message and the first.txt data file. "crashes" is not very descriptive, and without the data we cannot try the code.
Emily Takeva
2016-11-13
采纳的回答
更多回答（1 个）
Roger Stafford
2016-11-13
编辑：Roger Stafford
2016-11-13
0 个投票
1. In the expression for ‘p2’ you have “t/tau” which is matrix division. However the sizes of ’t’ and ‘tau’ are incompatible with matrix division. Probably you need -t./tau.’ . (That's a transpose operator on tau to make it a column vector.)
2. I also have serious doubts about the validity of taking the sum in calculating both ‘p1’ and ‘p2’. It makes a very strange kind of integrand. You are already summing over your data in obtaining each individual integrand value as ‘L0’ and ‘A0’ vary.
3. Also why did you define ‘L0’ and ‘A0’ as vectors earlier, while using the same symbols for arguments in ‘p1’ and ‘p2’? It suggests some kind of erroneous thinking in 2. above.
2 个评论
Emily Takeva
2016-11-13
Roger Stafford
2016-11-14
Did you transpose tau as I specified using tau.'?
类别
在 帮助中心 和 File Exchange 中查找有关 Logical 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
