Steven Lord

Last seen: Today

MathWorks

4,781 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
How to create a matrix with several days using eval fuction?
There's no need to use eval here, and in general if you feel you need to use eval that's often a code smell. To assemble text u...

4 hours ago | 0

Answered
undefined function or variable 'basefilename'
The variable basefilename used on line 8 of your code is not the same as the variable baseFileName defined on line 7. Case matte...

9 hours ago | 0

Answered
debugging limit Error using sym/subsindex
The code you posted is not the code you ran. What you said you ran was: syms k f = 2*l1^k*v1 + 1*l2^k*v2 + 3*l3^k*v3 ...

10 hours ago | 0

Answered
Variable precision arithmetic in ode45 and others?
What types of differential equations are you trying to solve that you need to use arbitrary precision arithmetic? If you're try...

11 hours ago | 0

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Matlab having problem interpreting streamed string into numbers.
Please remove the semicolon from the end of this line, let your callback trigger a few times, and show us exactly what gets disp...

1 day ago | 0

Answered
What does this syntax mean? “yyy(1,1) logical = xxx”
See this documentation page for information about the property validation syntax used in properties blocks inside a classdef fil...

1 day ago | 0

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How to quickly update the inverse for a sparse matrix when a row changes?
You can't even be confident that A1 is invertible. A = speye(5) invA = inv(A) A1 = A; A1(3, 3) = 0 % changing one element ...

2 days ago | 0

Answered
How to stop cyclic program in Matlab online - timer
Let's go through your function line by line. function start () fileID = fopen('exptable.txt','w'); a = timer; se...

3 days ago | 0

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sorting table according to date/time
which failed, probably becasue I am not defining the AM/PM symbols. According to the table in the description of the Format pro...

3 days ago | 0

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How to fix it.
So you want to take 5001 values and generate 25005 (5001 times 5) values using those values. How do you want to generate the add...

3 days ago | 1

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Answered
Why does rem(a, b) function give different answers for input values' class 'double' and 'uint64'?
Let's look at the value stored in a1 converted to a uint64. >> a1 = 9419588158802421600; b1 = 44; >> a2 = uint64(9419588158...

3 days ago | 1

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Answered
Why does rem(Centnum,5) give me an answer that is not zero?
>> x = 7.45; >> d = floor(x); >> c = x-d c = 0.45 >> cn = 100*c; >> cn - 45 ans = 1.4210854...

3 days ago | 0

Answered
Roll a 6-Sided Die and Compute the Probability of the Sum (with bar graph)
function prob = ex4(n) % % rng('shuffle') prob = zeros(1,12); TotalNRolls = 0; while TotalNRolls <= n Conceptual question...

3 days ago | 0

Answered
Track Simulink slx Files
This documentation page includes instructions on how to configure source control tools to use tools provided by MathWorks to dif...

3 days ago | 0

Answered
How do I perform fft for each column in a matrix?
If you want to make it explicit that you're operating down the columns, from the documentation page: "Y = fft(X,n,dim) returns t...

3 days ago | 0

Answered
Workaround on curvefit limitation
The built-in library of fits only contains sum of sines and Fourier fits up to sin8 and fourier8. If appropriate you could write...

3 days ago | 1

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Answered
how to using single editor in matlab2020a
As stated on this documentation page "At the upper right of the tool panel, click [the downward pointing triangle in a circle], ...

4 days ago | 0

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Invalid use of operator.
Let's play "Count the parentheses". The way to play: Start a counter at 0. Whenever you see a ( add 1 to the counter. Wheneve...

4 days ago | 0

Answered
A variable saved in a structure as a mat file in 2018b seems unreadable in 2020b
If the definition of the Defect class is not available when you try to load it from the mat-file how would MATLAB know how to co...

4 days ago | 1

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Answered
table2timetable adding time vector with start- and end date
The times for a timetable can be either a datetime array or a duration array. Turn your data into a duration array and use it to...

6 days ago | 0

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Answered
char to double data type
I recommend turning the character data representing dates into a datetime array and using that datetime array along with your do...

6 days ago | 0

Answered
Can I store a function including multiple variable?
You can't call a function handle using :. If you want the anonymous function to "remember" and use the values of x and t that yo...

9 days ago | 0

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Hi, I want a solution regarding below error.
Google found only one hit for mk_egs_string. It was this question. So this is not a MathWorks function, nor is it a function on ...

9 days ago | 0

Answered
I have matrix A, calculate null(A) but then A*null(A) doesn't give me 0?
Note that the description of the output argument on the documentation page for the null function does not include the character ...

9 days ago | 0

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Is there such a table units identification approach?
Let's make a sample table and give it some units: >> load patients >> patients = table(LastName,Gender,Age); >> patients.Prop...

10 days ago | 0

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Answered
How to find what settings "tsne" is using when I do not specify any Name Value pairs as options?
Open the documentation page for tsne using the doc command. Scroll down to the Name-Value Pair Arguments subsection of the Input...

10 days ago | 0

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Answered
Why matlab live editor and matlab script gives different rank calculation result for the same matrix ?
The value MATLAB displays is sometimes not the value MATLAB uses in computations. >> format short >> x = 1 + 1e-8 x = 1....

10 days ago | 1

Answered
MATLAB CODE COVID-19
This is not at all what I'd call a trivial task, given the number of papers and stories on the MathWorks COVID-19 R&D page. At a...

10 days ago | 0

Answered
Help me read the doc on matlab.fonts Settings
What is the purpose of TemporaryValue ? The name itself indicates that its value will only be used for a limited time. Setting ...

10 days ago | 0

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Answered
Loading C files in matlab with mex
I'm not familiar with that package but I'm curious if the ilu function in MATLAB would be suitable for your needs?

11 days ago | 0