# Walter Roberson

I do not do free private consulting. If you want to bring my attention to something, send a link to the MATLAB Answers location. I am currently caught up to T0099119; if you are waiting on a reply from me for an older issue, please send me a reminder.

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**Content Feed**

Error: Unrecognized function or variable 'getMatchedFilter'.

The input to getMatchedFilter must be a phased-encoded waveform object, but instead you are just passing in double precision arr...

2 hours ago | 0

Appending multiple Excel files using script

input_dir = '/MATLAB Drive/Project11/xin'; %directory excel files are stored in input_extension = '.xlsx'; %or .xls output_...

3 hours ago | 1

Error: Insufficient number of outputs from right hand side of equal sign to satisfy assignment in ft_read_mri

ftver = tmp.Version; Somehowm, tmp is an empty struct or object (that does have a field or property named Version) . Rememb...

11 hours ago | 0

Why the audioread function is giving data samples in two coloum?

That indicates that the audio has two channels (stereo)

11 hours ago | 0

How to make the question reappear if someone mess up with the number ? eg. 0 to 4. And then someone type 5.

while true ques_1 = input('\nIn the last month, how often have you been upset because of something that happened unexpected...

15 hours ago | 0

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how to do pcolor plots from 3d data?

x=100; y=100; z=100; r = randi([1 5],x,y,z); cmap = [0 0 0; 1 0 0]; mask = double(r(:,:,60) == 1); imagesc(mask, 'AlphaDat...

16 hours ago | 0

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how to discretize the 3-D surface into individual points in MATLAB

F = @(X, Y) sin(X).^2 - cos(3*Y).^2; %equation of the surface xvec = -1:0.1:1; yvec = -3.2:.1:3.2; [x, y] = meshgrid(xvec...

16 hours ago | 0

imread, reshape and zeros function syntax problems

imread() returns the data type stored in the file. The most common data type stored in image files is uint8(), but there are oth...

17 hours ago | 0

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circshift function working explanation needed

M = (10:10:40).' + (1:9) circshift(M, -1) You can see that this is the same as [M(2:end,:); M(1,:)] And more generally, circ...

22 hours ago | 0

How to save image after encryption?

My suspicion would be that your original image is uint8 and that when you did the encryption, you did not make sure to create ui...

22 hours ago | 0

Solving Equaiton with multplying power

syms A B C syms X Y Z integer eqn = (B*C^-1)^X * (B)^Y * (A*B^-3)^Z * (B^3*C^-1) == A^0*B^0*C^0 seqn = simplify(lhs(eqn)) == ...

1 day ago | 1

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Workspace Updates when script is complete?

Correct. Generally speaking, there would be too much overhead to continually update the workspace browser when you are not stop...

1 day ago | 0

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Overlay gray ROI on an image

newI(row1 : row2, col1 : col2) = repmat(GrayRoi, [1 1 size(newI,3)]);

1 day ago | 0

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read/write csv file

dlmwrite() offers the option -append . Note, however, that this is restricted to writing additional rows immediately after all ...

1 day ago | 0

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call a variable in a timetable from a cell matrix

for 1 = 1:10 a(:,i) = Timetable.(VariableNamesMatrix{i}); end But you should consider just using a = table2array(Timetab...

2 days ago | 0

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python to Matlab udp communication

https://www.mathworks.com/matlabcentral/answers/319729-how-can-i-receive-udp-broadcast-data-in-matlab-using-instrument-control-t...

2 days ago | 0

Issue with native2unicode and windows-1252 encoding

source = char(0:511) bytes = unicode2native(source, 'windows-1252') backport = char(bytes) whichdiffer = find(source(1:256) ~...

2 days ago | 0

Horizontal concatenate in UItable table

oldData(i)={horzcat(oldData{i,:})}; Let us look at what that is being asked to do for i == 1: oldData(1,:) = ...

3 days ago | 0

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Saving plot as a GIF

%This code assumes that you might be changing x inside your loop. If x is %constant then it can be done a little better. fil...

3 days ago | 0

Solving an equation with two vectors

You have 37411 equations in one single variable. There is no value, p, such that all of the equations are satisfied simultaneous...

3 days ago | 0

How to generate a rhythm that is based on an algorithm in matlab?

a = 5, b = 13 positions = floor(linspace(1, (b+1), a+1)) rhythm = zeros(1,b); rhythm(positions(1:end-1)) = 1

3 days ago | 0

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Why does my function not return a figure when there is no error but when there is it returns a figure?

Change h = polarhistogram (deg2rad(x),deg2rad(y); to h = polarhistogram(deg2rad(x), deg2rad(y));

3 days ago | 0

Time arithmetic (no dates)

tdiff = (hours(4)+minutes(30)) - (hours(2) + minutes(45)) [h, m, s] = hms(tdiff)

3 days ago | 2

Can anyone please help me out to obtain frequency Modulated wave from a Phase Modulator using pmmod function in matlab?

fs = 50; t = (0:2*fs+1)'/fs; x = sin(2*pi*t) + sin(4*pi*t); fc = 10; phasedev = pi/2; tx = pmmod(x,fc,fs,phasedev); ...

3 days ago | 0

its ask to prelocate speed on p line. why?

Why? In most circumstances, MATLAB does not examine the context to figure out how many iterations of a loop will be done, and s...

3 days ago | 0

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How to find a proper algorithm to solve this optimal control problem?

You did not say what you wanted to optimzie with respect to. If you wanted to optimize with respect to u, then see solu below. ...

3 days ago | 0

Unrecognized function or variable 'gca'

Summarizing: gca was being assigned to as a variable. With current versions of MATLAB, if you assign to a variable that has the...

3 days ago | 1

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I am trying to find values of four constants from four equations. Yet the code is unable to give out values

When I try your code, I get all 0 for the constants. When I go through step by step from the equations, I get the same result...

4 days ago | 0

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Unrecognized field name in solving symbolic matrix

You did not specify which variables to solve for, and you have more variables than equations. solve() choose variables to solve ...

4 days ago | 0

| accepted