Error trying to solve 2 Second ODE
Just looking at func.m, it appears you pass in a 4-element x vector, but you only return a 2-element a vector. You need to retu...

24 Tage ago | 0

vpa doesn't seem to work
You are passing a double into vpa( ), so your precision is lost before you even call it. You could pass in a string instead: n ...

26 Tage ago | 1

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A function to find prime number
Your function doesn't return anything, so when you try to use its output you get an error. Change this: function isPrime(numbe...

26 Tage ago | 0

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Rolling all six numbers on a six sided die
This: v = zeros(1,NToys); NRolls = 0; needs to be inside your Trial loop so that it resets for each trial. A simpler way to ...

27 Tage ago | 0

Need help Euler Method
The fundamental thing you are doing wrong is that you don't have the proper size state vector. For a 1st order equation, the st...

27 Tage ago | 0

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How can I add values of an array as an input into the ode45 function ?
What is the size of I? What is the DE you are solving? Maybe just dropping the (t) will work: dydt= (-I/(3600*Q)); Or maybe ...

27 Tage ago | 0

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double differentiation and double integration of sine wave
"... when differentiating my position to get velocity and acclereation i did work out all three of them by hand, quite sure it i...

27 Tage ago | 0

Comparison of two Vektors with different size to find variables
E.g., x = ismember(b(:,1:2),a(:,1:2),'rows'); c = b(x,:); Depending on how the times were constructed, you might need to use ...

27 Tage ago | 0

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How to transfer parameter between C and fortran
Maybe the Fortran compiler settings are compiling the default integer as 8-byte integers. Try forcing the Fortran to use 4-byte ...

27 Tage ago | 0

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How to sort a matrix in a random order
E.g., >> x = reshape(1:24,4,6) x = 1 5 9 13 17 21 2 6 10 14 18 22 3 7 ...

28 Tage ago | 0

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can someone help me to solve this error (This statement is not inside any function. (It follows the END that terminates the definition of the function "RK4".)
Looks like your plot( etc ) and legend( etc ) lines are stuck inbetween two functions. Did you intend them to be inside a scrip...

28 Tage ago | 0

making array in for loop
Maybe prior to the loop define Alignment as a cell array to hold your results: Alignment = cell(10000,1);

etwa ein Monat ago | 0

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A uniform random number between a and b is: u = a + rand*(b-a) Generate two of these with a = -0.05 and b = 0.05 and then do t...

etwa ein Monat ago | 0

Can someone explain the concept of B= null(A) in simple words?
The columns of B form basis vectors for the "null space" of A. Any linear combination of the B columns, when multiplied by A, w...

etwa ein Monat ago | 1

Unable to perform assignment because the size of the left side is 1-by-1 and the size of the right side is 5-by-1.
Looks like Cd and rho are vectors. So the result of those calculations on the right hand side will be vectors. But you are tryin...

etwa ein Monat ago | 0

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What can I use instead of VPA?
See the following FEX submissions by John D'Errico: https://www.mathworks.com/matlabcentral/fileexchange/36534-hpf-a-big-decima...

etwa ein Monat ago | 1

Two equal datetime values showing as unequal when compared?
This is often just a display issue. E.g., >> s = datetime(2017,3,24,9,5,0.1) s = 24-Mar-2017 09:05:00 >> t = datetime(20...

etwa ein Monat ago | 0

How can I multiply square submatrices more efficiently?
Here is the naive mex code. Could probably be made faster by doing the for-loop in parallel or trying to optimize cache hits, b...

etwa ein Monat ago | 1

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big difference in execution time in approximately the same code
The matrix multiply operator * in MATLAB calls highly optimized compiled BLAS library code in the background. The BLAS library ...

etwa ein Monat ago | 2

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This is a question from numerical methods asking to explain what the code does for 12 marks.
https://en.wikipedia.org/wiki/Newton%27s_method

etwa ein Monat ago | 0

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how to use passing by value and passing by reference
In the background, MATLAB effectively passes all variables into functions as shared data copies. This has the same effect as pas...

etwa ein Monat ago | 0

matrix dimensions must agree error
Well, tau is only two elements and w is a lot more than that, so you can't multiply them element-wise like you are attempting to...

etwa ein Monat ago | 0

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Monte Carlo integration of sin(x)
This is what you are currently doing with the "random counting in an area" method: To make it go from -1 to +1 instead, you c...

etwa ein Monat ago | 0

How can i split the values of vector into group of 5?
Assuming your vector is divisible by 5, you could do this: v = your vector g = reshape(v,5,[]); % reshape v into a 5 x N matri...

etwa ein Monat ago | 0

Runge-Kutta function with a second order ODE
I'm still confused about your initial conditions and what y0 and y1 are. But let's back up a bit. For a 2nd order ODE, your st...

etwa ein Monat ago | 0

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how to call struct array in subroutine

etwa ein Monat ago | 0

For and if loops
RT([3,6],v) is the syntax to use for the 3rd and 6th rows of the v'th column of RT. But this is of course going to be two eleme...

etwa ein Monat ago | 0

Matlab Solving Differential Equation using Runge Kutta
In this line: k_1 = F_xy(x(i), xy(i)); You've got xy(i) as an argument, but there is no xy variable. I think you meant y(i) h...

etwa 2 Monate ago | 0

How can i write MacLaurin Sequence for 1/1+x2
An outline of your code could look something like this: x = _____; % you fill in the blank here, or get an input from the user ...

etwa 2 Monate ago | 0