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# Walter Roberson

##### Last seen: Today
46.490 total contributions since 2011

I do not do free private consulting. If you want to bring my attention to something, send a link to the MATLAB Answers location.

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Help with "Dimension 1 is fixed on the left-hand side but varies on the right ([1 x 1] ~= [:? x 1])" error r2018a.
function plantOutput = modIndex(gridVoltage, setPoint) After that line add assert() statements that test that each of the ...

etwa 6 Stunden ago | 0

Evaluate definite integral numerically, where the function is indeterminate
Break the integration up into parts that are piecewise numerically integratable, and add the parts together. Do not, however, ex...

etwa 6 Stunden ago | 0

Passing a matrix as a parameter in ode15s
function dvdx = ode_x(x,vx,vfx) dvdx = reshape(vfx./reshape(vx, size(vfx)) - 1), [], 1); end

etwa 6 Stunden ago | 0

Is there a non-eval based solution to effectively getting the output of disp as a string value?
You can use diary() to have the output of disp copied to a file, then turn diary off and read the file. This will not be any bet...

etwa 7 Stunden ago | 0

"As you know, Oracle doesn't allow JRE for commercial use without a license anymore." Not exactly correct. The restrictions a...

etwa 9 Stunden ago | 0

How to create a large matrix using another matrix
https://www.mathworks.com/help/matlab/ref/spdiags.html#mw_6de431d3-8887-4b16-b947-86a610ddea8c

etwa 9 Stunden ago | 1

ressistors with small random offset in SIMULINK
The attached model is adapted (solver parameters updated) from the File Exchange Contribution SERIES AND PARALLEL CIRCUITS, ver...

etwa 17 Stunden ago | 1

Triangle fitting using fminsearch
Guessing about what you were trying to do with that fT stuff: function FW = gaussplustriangle(x,x0,y,isPlot) %x0 is fixed cente...

ein Tag ago | 0

Find Fundamental Frequency to know if it´s a Man or a woman or children
Your project is not possible to complete using any known science. Suppose for example that group A has a mean score on somethin...

ein Tag ago | 1

Why are the results different when calculating a 10 x 3 matrix and a 1 x 3 matrix?
XYZ_rwd21t = [1.30937778204061e-14,-13.8617246105272,22.6275000000000; XYZ_rwt212t(i, 2) = XYZ_rwd21t(1, 2); Okay, so ...

ein Tag ago | 1

fminsearch for ligistic fit
f2 = @(p)f(p,x); That relies on x existing in your workspace. If you are going to do that you might as well assume it on the...

2 Tage ago | 0

Adding elements of a vector in matlab
fliplr( cumsum( fliplr(a) ) )

2 Tage ago | 0

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Integration from 0 to a variable.
integral() is for numeric integration, but solve() is for symbolic work. fun2=@(x)((s-x).*((b/a).*((x/a).^(b-1)))/(1+((x/a).^...

2 Tage ago | 0

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fprintf to plot error

2 Tage ago | 0

Divide .wav file into equal segments
The below will split all .wav in a given directory into 3 second buffers. A directory named after the file will be created insid...

2 Tage ago | 1

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How can I make a non uniform quantization of an image?
If you have the Communications toolbox you can use quantiz() https://www.mathworks.com/help/comm/ref/quantiz.html You can also...

3 Tage ago | 0

MATLAB Online is not free; you need to have an active account of one of several kinds. If Harvard has a Total Academic Headcoun...

3 Tage ago | 0

Y axis in scientific form
If you are referring to the scale factor that sometimes get put up near the top of the Y axes, then the answer is that there is ...

3 Tage ago | 0

solve vs. fsolve
Sometimes plotting and finding intervals by eye is not productive. In the general case, theory says that it is impossible to c...

3 Tage ago | 0

Make matrix with loop
In the general case: xvals = [list of x values, does not have to be regularly spaced or even sorted]; numx = length(xvals); y...

3 Tage ago | 0

Plot Not showing all values
The max value of col2 is only about 20, but the maximum value of col1 is 992008 Near 210 the entries go like 21.4239 21.5239 ...

3 Tage ago | 0

Multi Threads operation SERIAL PORT in Parallel
That cannot be done with asynchronous serial ports such as RS232 and USB. In order to synchronize reception of data, you need to...

3 Tage ago | 0

how to insert value of array to other array
horzcat(). [list of values] is also horzcat()

3 Tage ago | 0

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What am I missing in this code I am trying to find roots of a System of Equation?
x=x+transpose(eps) That should be subtraction rather than addition.

3 Tage ago | 1

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Unable to perform assignment because the indices on the left side are not compatible with the size of the right side.
inv(j)*f is going to return a column vector. Your original X0 is a row vector. Since R2016b, if you subtract a row vector and a ...

3 Tage ago | 1

Function that calls another function in LiveScript
Yes, provided that you are using a MATLAB release new enough to support functions in Live Scripts (which you are.) Note that th...

4 Tage ago | 0

cumulatives of the dynamical system
You currently have a first order differential equation, diff(D,t) == x(t). When you use it with ode45 you would be using a funct...

4 Tage ago | 0

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Efficiently ways to solve for multiple for loops, of which the indices are the parameters of a function
You can do at least part of it in vectorized form. The following deliberately creates random numbers in the same order as if yo...

4 Tage ago | 0

How do I define an empty table of unknown size?
Sorry, variables that do not exist do not have any datatype. As you add variables to the table, the datatype associated with t...

4 Tage ago | 0