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# Tianlan Yang

Last seen: meer dan een jaar ago Active since 2021

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I cannot use the lugauss function to calculate L and U factors from matrix A. Please help!
I have attached my operating code and here is the lugauss funciton: function A=lugauss(A) %LUGAUSS LU factorization without pi...

meer dan een jaar ago | 0 answers | 0

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Question

Please help to look at the code below(2)
I want to get the max and min value of the equation, using the last three lines of code. BuI I don't know what's wrong with th...

meer dan een jaar ago | 0 answers | 0

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Question

Please help me to look at the code below. Thx
I want to get the max and min value of the equation, using the last three lines of code. BuI I don't know what's wrong with th...

meer dan een jaar ago | 1 answer | 0

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Question

Please help me to look at the code. Thx
I don't know what is wrong with that code. Here is the screenshot of the issue and the code: function intGL=gausslegendre (a,...

meer dan een jaar ago | 2 answers | 0

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Question

I am trying to compute the zero of a function using fzero, but the system always says my function must be finite and real. How can I solve that? Thank you!
I want to find the zero of f(x) = 2(3x+4)(x^3+4x^2-10)/(x^2(3x+8)^2) Here is the screenshot for the error:

meer dan een jaar ago | 1 answer | 0

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Question

Can someone please help! I cannot plot this graph.
x=[-0.1:0.1]; y=35000000*x+401000./x-17122.7./x.^2-1494500; figure plot(x,y) legend('y') I think my function is correct, bu...

meer dan een jaar ago | 2 answers | 0

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Question

Please help! How to use the vector z (the component of b orthogonal to ColA) to calculate the distance from b to ColA by using built-in function norm?
Theory: When the columns of A are linearly independent, a vector p is the orthogonal projection of a vector b∉ Col A onto the Co...

bijna 2 jaar ago | 0 answers | 0

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Question

Please help! How to express p as the projection of b onto the Col A according to the theory. I know that the component of b orthogonal to ColA is z=b-p(accodfing to the theory )
function [p,z]=proj(A,b) format A=shrink(A); m=size(A,1); p=[]; z=[]; boolean = true if ~isequal(size(A,1),size(b,1)) di...

bijna 2 jaar ago | 0 answers | 0

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Question

Please help me solve such problem. I know why I get this error （because it is not a square matrix）. However, the data (4*3 matrix) given by my tutor cannot be changed, how to make it run? Thank you.
here is the function: function [L,U] = eluinv(A) [m,n]=size(A); [L,U] = lu(A) LU = roundingfixer(L*U); if (A == LU) dis...

ongeveer 2 jaar ago | 1 answer | 0

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Question

Why do I get this error?
Here is the function: function [X1,X2,X] = msystem(A,B) [~,n] = size(A); [~,p] = size(B); [L,U] = lu(A); %solving for X1 ...

ongeveer 2 jaar ago | 1 answer | 0

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Question

There is an error in my code
Here is the function: function [L,U] = eluinv(A) [~,n]=size(A); [L,U] = lu(A) LU = roundingfixer(L*U); if (A == LU) dis...

ongeveer 2 jaar ago | 1 answer | 0

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Answered
Error "Matrix dimention must agree"
Thank you. Could you please look another question I post?

ongeveer 2 jaar ago | 0

Question

Error "Matrix dimention must agree"
Here is the function: function [L,U] = eluinv(A) [~,n]=size(A); [L,U] = lu(A); format compact if closetozeroroundoff(A,7)...

ongeveer 2 jaar ago | 2 answers | 0

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There are two errors in my code. Can someone know how to edit it to maker it run? Thank you!
Here is the function: function [L,U] = eluinv(A) [~,n]=size(A); [L,U] = lu(A); format compact if closetozeroroundoff(A,7)...

ongeveer 2 jaar ago | 1 answer | 0

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Question

Can someone help solve this Error? Thank you.
Here is the function: function [L,U] = eluinv(A) [~,n]=size(A); [L,U] = lu(A); format compact if closetozeroroundoff(A,7)...

ongeveer 2 jaar ago | 0 answers | 0

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Question

Can someone solve this Error for me? Thank you
Here is the function: function [L,U] = eluinv(A) [~,n]=size(A); [L,U] = lu(A); format compact if closetozeroroundoff(A,7)...

ongeveer 2 jaar ago | 1 answer | 0

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Question

Error "Matrix dimensions must agree" in the line "T = norm(rref(Y)- rref(U)) < tol;" I used "A=[1 1 4;0 -4 0;-5 -1 -8; 2 3 -1] [L,U] = eluinv(A);" in my livescript. Thank you so much!
Here is the function.m: function [L,U] = eluinv(A) [m,n] = size(A); [L,U] = lu(A); B = L*U; C = closetozeroroundoff(B,7)...

ongeveer 2 jaar ago | 1 answer | 0

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Question

Why there is an error in my code after I type "[L,U] = eluinv(A);"? ( the error is that too many output arguments ) Thank you!
Here is the function: function [] = eluinv(A) [~,n]=size(A); [L,U] = lu(A); format compact %have to round to supress extra ...

ongeveer 2 jaar ago | 1 answer | 0

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