Vectorizing the addition of a vector of values with associated indices to an existing vector, when the vector of indices has repeated values.
Hi Nathan, sparse matrices automatically do what you want. You have full matrices, and sparse operations are on the slow side ...

etwa ein Monat ago | 0

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Sub-sampling the minimum number of points to accurately reproduce a curve
Hi Michael, take a look at the interp1 function. There are several choices for the type of interpolation, and assuming a curve ...

etwa ein Monat ago | 0

Cannot find ALL solutions to simultaneous equation
Hi CZ If exp(x^2+y^2+z^2) = 9 then x^2+y^2+z^2 = log(9) which is a lot less challenging for symbolic evaluation. clear all...

etwa ein Monat ago | 0

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Troubles assigning colorbar values in a bivariate histogram plot
Hi Mar, I have been looking at this with some data I made up, but now that you posted it I was able to plug it in. I thought y...

etwa ein Monat ago | 0

What to use instead of simple function?
Hi Liliana, 1/(2*pi^(1/2)*(1/(4*a^2))^(1/2)) may not be pretty, but it does equal a/sqrt(pi) so it is mathematically correct....

etwa 2 Monate ago | 0

a Simple Matrix question
Hello LC Matrix_C = matrix_A; Matrix_C(matrix_A == Matrix_B) = 255;

etwa 2 Monate ago | 0

How can I get more than 49 digits of pi in a string?
Hi India, vpa(pi,100) for example (although you need the symbolic toolbox for vpa) And see Walter's comment below. The answer...

etwa 2 Monate ago | 0

plot polygon function error
Hi msh, the reason is pretty simple. You are asking for an output from the function, but you have not provided any in its defi...

2 Monate ago | 0

why the legend show wrong lines ?
Hi tomer, try replacing plot(t,43*(19.6e-3)/(100*15e-3),' black '); %% plot--> of boundery limit with plot(t,43*(19.6e-3)/(...

2 Monate ago | 0

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Solving 3 Simultaneous Exponential Equations
HI Rory, just for completeness y1 = 159.2543; y2 = 117.2699; y3 = 63.8384; x1 = 291.15; x2 = 293.15; x3 = 299.15; A1 =...

2 Monate ago | 1

solve on vector equation
Hi Michiel, The unit vector N has to lie in the plane defined by s1 and s2. The result for any s1,s2 is N = s2 - (n1/n2)*s1;...

2 Monate ago | 0

how can I creat a matrix of all possible combinations of zero and ones across eight digits.
HI Yonatan, not a black box: function a = x10(ndigits) a = ['0';'1']; count = 1; while count < ndigits n = size(...

2 Monate ago | 0

IFFT of Convolution equivalence
Hi JOB/Ridwan Here is a small example where a and b are padded with zeros, so that regular convolution can be compared with con...

2 Monate ago | 1

Why 999^999-999^999 is NaN?
HI Fahmy, >> realmax ans = 1.7977e+308 That's the largest floating point number in Mallab, which uses IEEE754 64 bit double ...

2 Monate ago | 0

How to obtain CDF from the below PDF function
Hello Manesf, This pdf seems related to the Weibull distribution. I made some abrreviations Etta_d = xid Etta_D = xiD ...

2 Monate ago | 1

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In the matlab page of Associated Legendre Polynomials, is the example for the spherical harmonics correct?
Hi chaitanya, Good catch. Really good catch. In addition to the signs of the lobes, I believe that Matlab's Y32 is functional...

2 Monate ago | 2

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How to plot the velocity of a crate on a ramp for different angles?
Hi Kiera, The plot above shows the velocity of the box at the top of the ramp getting larger as the angle of the ramp gets stee...

2 Monate ago | 0

associated legendre functions matlab
Hi chaitanya, It's apples and oranges. When the domain of the argument is -1 <= x <= 1, the function is -sqrt(1-x^2). That's ...

3 Monate ago | 0

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Implementing a sum with summands of unequal spacing inside an integral
Hi Richard, I don't claim to be a professional although I did use Matlab at work, and here is how I would do this. The main th...

3 Monate ago | 1

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Does the permute function have a bug?
Hello ZY, see 'help permute'. Permute puts the dimensions in the order listed, so in this case the old 4th dimension goes firs...

3 Monate ago | 0

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Is it possible to create periodic boundary conditions for a matrix with linear indexing?
Hi Tom, mod(k,N)+1 for the raised index, k+1 mod(k-2,N)+1 for the lowered index, k-1 and these do give the correct vector of ...

3 Monate ago | 0

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how to solve the equation: xdot=AX+Bu; where u=sin(2t)
Hi Ebraheem, ode45 is fine with explicit time dependence in the calculation of xdot: [t, x] = ode45(@smc5,[0, 10],[1, -2]) pl...

3 Monate ago | 2

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Series expansion with Legendre polynomials
HI James, I won't address how one might print the result, but the mistake in the algrbra is that you should use y(i) = ((2*i+1...

3 Monate ago | 0

Chua Oszillator in Matlab, Chaos
Hi Albin, In your second version, the equation for xdot is dimensionally incorrect. Changing it to xdot = (1/C1)*(G*(y-x-g));...

3 Monate ago | 0

Meshing a complex function with limits
Hello Haider, for someone who is new to Matlab you are doing well. You just need a couple of changes. First, you forgot that r...

3 Monate ago | 1

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plot Gibbs phenomenon individually???
Hi Neptune, I agree that my comment on what the Gibbs phenomenon actually is was not very helpful to the actual problem at hand...

3 Monate ago | 0

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Automatic Complex Conjugate in ftt
Hello Ha Oe the quote command is not just the transpose, it's the complex conjugate transpose (Hermetian conjugate). For the s...

3 Monate ago | 1

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The input signal is complex conjugate, but the IFFT output is complex!
Hello yz, The problem is that to produce a real ifft, the first element of Ax, which is the f=0 term, has to be real since that...

3 Monate ago | 1

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Why is dsolve returning an arbitrary constant?
Hi David, you need slightly different syntax. syms y(t) g L c Dy = diff(y) S = dsolve(diff(diff(y(t))) -L*y - g == 0, y(0) =...

3 Monate ago | 0

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