Steven Lord

Last seen: Today

MathWorks

5,501 total contributions since 2002

I joined The MathWorks in the Technical Support department during the summer of 2001 and transferred into the Quality Engineering department in March of 2004. I now work qualifying the core MATLAB numerical functions (PLUS, MINUS, LU, FFT, ODE45, etc.)
Professional Interests: mathematics, MATLAB

For assistance with MATLAB question please post to MATLAB Answers or contact Technical Support using the Contact Us link in the upper-right corner of the page instead of contacting me directly.

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Answered
activation code for matlab 2016
If you have purchased MATLAB in the past, you should have been sent the activation code at that time. You should be able to ask ...

1 hour ago | 0

Answered
problem with name=value syntax
That syntax is intended as a way to specify name-value pair arguments. So instead of: plot(1:10, 1:10, 'Marker', 'o', 'LineStyl...

1 day ago | 2

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Answered
Script to remove polynomial/quadratic error off CSV data
The detrend function and/or the Remote Trends task may be of interest or use to you.

1 day ago | 0

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I need help with my thesis
The wblpdf function is part of Statistics and Machine Learning Toolbox. Check the information displayed by the ver function to d...

1 day ago | 1

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Changing Keyboard shortcuts in App Designer in MacOS
Go to the Preferences in the Environment section of the Home tab of the Toolstrip. Under MATLAB navigate to Keyboard then Shortc...

3 days ago | 0

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how take a mathematical function from user
What do you mean when you say you want "the user to enter" the function in your comment? Do you want the user to have to pass s...

3 days ago | 0

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Can you organize scatter plot points?
When I look at your plot it looks to me an awful lot like the boxplot thumbnail in the Plots tab of the Toolstrip. You may want ...

4 days ago | 0

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How to generate random graph of n vertices with random connections in matlab
Take a look at the sprand and sprandsym functions.

4 days ago | 0

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how to integrate a product with function handle
You can't calculate the product of a number and a function handle. What you can do instead is calculate the product of a number ...

4 days ago | 0

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Creating a new column in a table which is true or false
rng default id = (1:10).'; SIC = randi(3, 10, 1); t = table(id, SIC) t.is1or2 = ismember(t.SIC, [1 2])

5 days ago | 0

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Answered
Getting the error as "Undefined function or method 'syms' for input arguments of type 'char'" when trying to use syms
You likely don't have Symbolic Math Toolbox installed and licensed. Check the output of the ver function to see if it's installe...

5 days ago | 0

Answered
How to know the value of a variable in a past time in Simulink?
I think you want a Unit Delay block.

5 days ago | 0

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Answered
index in safe-title
Try: str = "title_" + t{n} saveas(gcf,str,'jpeg') This will attempt to convert t{n} into a string and concatenate the string ...

5 days ago | 0

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Answered
Where can I find the dijkstraShortestPaths() function?
We do not distribute the source code for that function. What type of modification were you hoping to perform on that function? ...

6 days ago | 0

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Answered
Vector sum of forces
Use the vecnorm function.

6 days ago | 0

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Error using sub2ind Out of range subscript how to solve this?
What's the index of the value in row 1, column 6 of a 4-by-5 matrix? sub2ind([4 5], 1, 6) Trick question, since a 4-by-5 matri...

6 days ago | 0

Answered
why is the variable order in a user defined function important in lsqnonlin optimisation?
Why does the order in the self defined function important for lsqnonlin fitting? For the same reason that trying to feed yourse...

6 days ago | 0

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Answered
Is there any maximum for the size of matlab table?
There are theoretical limits (based on limitations of the operating system's ability to address memory) that you are highly unli...

6 days ago | 0

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Linearly detrended and a 30-day running mean
See the detrend and movmean functions.

6 days ago | 0

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Equation Error Argument to dynamic structure reference must evaluate to a valid field name
The number 1 is not a valid struct array field name. S = struct('a', 1, 'b', 2) S.('c') = 42 % works S.(1) = -99 % does not w...

7 days ago | 0

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Answered
How to plot time format
Now you'd probably want to use a duration array. h = randi(3, 1, 10); m = randi([0 59], 1, 10); s = randi([0 59], 1, 10); D ...

7 days ago | 0

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How to call a private function in a static function in App Designer?
Nowhere in your static method have you defined the variable app. methods ( Static ) function xd = anaerob(~...

7 days ago | 0

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Answered
Interactive with graphics in GUI
ax = axes('ButtonDownFcn', @(varargin) disp('hi')); Click on the axes. MATLAB will display hi in the Command Window. Now add a...

7 days ago | 0

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Answered
Error while finding determinant
Do you by any chance have a variable named det in your workspace? If so you will not be able to call the det function until that...

8 days ago | 1

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Open Matlab editor while running from command line
We stopped shipping the standalone editor quite some time ago, long enough that I can't find it in the Release Notes. It's proba...

9 days ago | 0

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Anyone know why it isnt accepting my expression
You're missing two multiplication signs. This is not valid MATLAB code. 2(w+vk) You need 2*(w+vk)

9 days ago | 0

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Answered
How to use DATE Excel Function in Matlab vector calculations?
Don't work with serial date numbers unless you absolutely have to. Use a datetime array instead. dt = datetime('now') + hours(r...

9 days ago | 0

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Answered
Range of matrices?
Tsigma(k)= [c^2 s^2 2*c*s;... s^2 c^2 -2*c*s;... -c*s c*s c^2-s^2]; What's on the...

9 days ago | 0

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Answered
Match different time series with one date vector
Consider storing your time-based data as timetable arrays and use synchronize to synchronize the timetables to a specific date a...

9 days ago | 0

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Answered
How to tell solver that symbols are matrices
If you're using release R2021a or later and have Symbolic Math Toolbox, create a symbolic matrix variable using the syms or symm...

9 days ago | 0

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