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Olympic puzzle number one
# builtin('clear','clear') # You can delete the variable from the workspace window (highlight and press delete or right click...

etwa 14 Jahre vor | 3

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Avoiding inverse of a matrix
We usually write A\B instead of inv(A)*B. So if you're computing D - C*inv(A)*B, then write it D - C*(A\B). It's hard to predi...

etwa 14 Jahre vor | 0

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error using unique function
What type of data is in the cell array? When you use UNIQUE on a cell array, the only case that's supported is when the element...

etwa 14 Jahre vor | 0

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Can I use hexa address like '0xF2' value in Matlab?
Don't know anything about the second question. As to the first, because MATLAB does not have a hex format in the language, you ...

etwa 14 Jahre vor | 0

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Compare inv(X) Vs mex inv (X)
I think it's rather likely with a difference of that magnitude that you have left memory integrity checks on. Try >> cfg =...

etwa 14 Jahre vor | 1

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quadl with vector bounds
One option is to use ARRAYFUN >> arrayfun(@(b)integral(@(x)x.*sin(x),0,b,'abstol',1e-5,'reltol',1e-5),0:3) ans = ...

etwa 14 Jahre vor | 0

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How to make a FOR loop to be efficient
There is no way to do what you ask, and it would not help you much if there were. What is it that that you're really trying to ...

etwa 14 Jahre vor | 0

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Numerical integration
If I understand the question properly, given a function f(x,y) and integration limits a <= x <= b, g = @(y)integral(@(x)f(x...

etwa 14 Jahre vor | 0

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integrate function
The problem has nothing to do with the integrator, rather with the way you have written the integrand: >> a = 1; b = 1; ...

etwa 14 Jahre vor | 1

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Using integral function for a function which is defined with an integral
>> phi = @(r)arrayfun(@(x)integral(@(t)exp(-t.^2./2),-inf,x),r); >> phi(-3:3) ans = Columns 1 through 5 0.003...

etwa 14 Jahre vor | 0

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quad2d precision?
I don't know what "60-100%" accurate means. Perhaps it would help to give a few examples of results that you regard "inaccurat...

etwa 14 Jahre vor | 0

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integration
I never quite know what to say when questions like this come up. There's nothing wrong with wanting to do integrals analyticall...

etwa 14 Jahre vor | 2

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Integration using a vector as function parameter
Not sure of your intention. This is how I interpreted what you wrote: >> N = 1:4; >> Crush = @(x,n) x.^n; >> integra...

mehr als 14 Jahre vor | 0

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matlab embedded fuction in simulink
I don't know anything about XSteam, but whenever you use an extrinsic function call, you need to pre-declare the output so that ...

mehr als 14 Jahre vor | 3

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numerical integration
You can't just integrate over the singularity near x=0.66. That's why you're getting the wrong answer.

mehr als 14 Jahre vor | 0

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Problem using the defined function triplequad
TRIPLEQUAD requires constant limits. You cannot have bounds that depend on integration variables. If you have R2012a, try INTE...

mehr als 14 Jahre vor | 0

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surface integral computation.
You should never expect an exact result from a numerical integrator. Even when there is no discretization error, there can be s...

mehr als 14 Jahre vor | 1

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problem with integrand and quad2d
Look at the definition of Vs. If you raise a negative quantity to a non-integer power, you get a complex number. The integrand...

mehr als 14 Jahre vor | 0

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Using quadgk inside a loop
You've got a couple of problems here that jump out at me. One is that your expression for n0 tends to lose precision due to the...

mehr als 14 Jahre vor | 0

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Using quadgk inside a loop
I agree with Richard. We'll probably need to see one of your attempts, but I can take a guess. Most likely you're having troub...

mehr als 14 Jahre vor | 0

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Integration of a function from R^1 to R^n
The integral of a vector-valued function is vector-valued. You simply integrate each component. This can be done with QUADV or...

mehr als 14 Jahre vor | 0

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Matlab Coder : codegen for mvnrnd
Instead of using sigma in that -args list, use sigma_type = coder.typeof(0,[2,2],[true,true]) This means the type is doubl...

mehr als 14 Jahre vor | 0

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integration using quadgk() in the complex plane
I'm going to assume this is a homework problem. Complex integrals generally depend on the path chosen. Here you want to go fro...

mehr als 14 Jahre vor | 0

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problem with double integral, dblquad and quad2d
syms ne me epsilon eta zeta; K1=76*10^9; K2=150*10^9; G1=26*10^9; G2=78*10^9; Vs=(((zeta/2)+(1/2))^ne)*((eta/2)^me); ...

mehr als 14 Jahre vor | 0

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in simulink, how to call functions (such as "quadv") which need to call function handles
First, regarding QUADV in particular, the MATLAB Function Block supports QUADGK. You may find that it is competetive to call QU...

mehr als 14 Jahre vor | 2

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Integration of some function containing a singularity
QUADGK has no trouble when t=1, but for t=2,3,4,... the correct answer, if I am not mistaken, is Inf. You were expecting QUADGK...

mehr als 14 Jahre vor | 0

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Double integration
If you have the 2012a release, just use INTEGRAL2: >> a = 2; b = 3; m = 2; n = 3; c = 2; d = 3; >> f = @(x,y)exp(-a*x-b*...

mehr als 14 Jahre vor | 2

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weird Problem with dblquad
The integrator QUAD (which is called in a nested way by DBLQUAD) has an internal limit on the number of function evaluations it ...

mehr als 14 Jahre vor | 0

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Large error between exact analytic answer and numeric integration
Your formulation has many problems. I don't see that you're using a mass matrix with ODE45, and you also have not inverted M, a...

mehr als 14 Jahre vor | 0

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Problem with matlab, simpsonrule
Looks to me like you're just running out of floating point precision. Double precision has about 16 decimal digits max, and you...

mehr als 14 Jahre vor | 0