Steven Lord

Last seen: Today

MathWorks

5,243 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 write a short syntax for the legend?
Set the DisplayName property of each line just like you set the LineWidth. Then legend show will make the legend appear and use ...

43 minutes ago | 0

Answered
hour of datenum type
What is the full and exact text of the error messages they receive? Show all the text displayed in red (and if there is any text...

4 hours ago | 0

Answered
Solve system of linear equations ...matrix output is not as expected
A being a 9-by-9 matrix is correct. syms A11 A12 A13 A21 A22 A23 A31 A32 A33 real; eq1 = A11*-0.001179+A12*-6.581+A13*0.008...

9 hours ago | 0

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Answered
How can I do to enable zoom only for a specific axes?
Call zoom with an output. Call setAllowAxesZoom on that object. See the "Object Functions" section on the documentation page for...

11 hours ago | 0

Answered
Task: write matlab code for a class MinAngle which calculates the minimum angle between two bearings (bearing A and bearing B).
The assignment operator in MATLAB is =. The element-wise comparison operator is ==. But you should use neither of those in your ...

13 hours ago | 0

Answered
Switching between open files in editor by searching
There is an API you could potentially use for this sort of task. I have my installation of release R2019b open, so I'll just ope...

13 hours ago | 0

Answered
Integral Function inside while loop only works for certain values. ArrayValued results in empty volumn vectors.
You probably want to recompute S *while* it is empty not *if* it is empty. Otherwise S could still be empty after the second vpa...

23 hours ago | 1

Answered
how do I take the matrix A and a vector with the indexes of the rows to be considered, and takes out a vector of the mean values?
function A(meanValue) = HW3Part3Function A(meanValue) = mean((A(1:2:end,:),2)) When you define your function, the function dec...

1 day ago | 0

Answered
convert logical values to numeric values
What do you want the double array to represent? Just 0 and 1 instead on false and true? Use Jan's approach. 0 where there isn'...

1 day ago | 0

Answered
Syntax Question, Why does this equal zero?
What happens if you compute it by hand? Start with the expression in the parentheses since they're at the top level of the opera...

2 days ago | 0

Answered
Can I assign a variable to a number in a matrix from another matrix?
There's a way to do this without creating 2*n individual variables. A = magic(7); E = eig(A); w = E(1:3); m = [3; 11; -7];...

2 days ago | 0

Answered
Not Enough Input Arguments
Your function can be called with at most two inputs, and since it uses both inputs on the line you called out it must be called ...

2 days ago | 0

Answered
Convert Text into Date Format
If you have a number: x = 196307; datetime(100*x+1, 'ConvertFrom', 'yyyymmdd') If you have text: y = string(x); datetime(y,...

2 days ago | 1

Answered
represent a function in Matlab
Let's look at your function symbolically. xo = 400; yo = 7000; x = 260; y = 6954; a = 0.5; b =0.4; K = b*xo-a*yo; % t=...

2 days ago | 0

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Answered
Fit operation with defined variables
See the "Create Fit Options and Fit Type Before Fitting" example on the documentation page for the fit function. It uses the 'pr...

3 days ago | 1

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Answered
Array indices must be positive integers or logical values.
If x only has one element, x(end-1) is an attempt to access element 0 of x. Arrays in MATLAB don't have an element 0. Their firs...

3 days ago | 0

Answered
How to define these two functions?
The name gamma already has a meaning in MATLAB, and in fact it calculates the function you're trying to evaluate with your anony...

3 days ago | 1

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Answered
How do I calculate this definite integral in matlab
When I encounter a problem integrating, one of my first thoughts is to look at the function I'm trying to integrate over the int...

3 days ago | 1

Answered
use vector as input
So you want to compute the value of e and the time required to compute that value for each element of n? A couple of suggestions...

3 days ago | 0

Answered
How to extend the colon operator for my own class
The colon function in MATLAB for numeric inputs does not return an iterator, it returns a vector. See the documentation page for...

3 days ago | 0

Answered
Invalid Simulink object name: loader &&& xPC：unable to load dependent module FAST_Library_Win32.dll @ MathWorks Support Team
Since you've mentioned MathWorks Support Team in the title of this question, it seems like you're looking for help from Technica...

3 days ago | 0

Answered
How do you create a composite function in matlab?
f = @sin; g = @cos; % define it two different ways fg = @(x) f(g(x)); h = @(x) sin(cos(x)); % Compare the two approache...

3 days ago | 0

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Answered
Comparing elements of one vector with multiple values in a matrix of different size
If the rows in A are sorted and disjoint, this does seem like a job for histcounts. Just ignore the bins representing the spaces...

3 days ago | 1

Answered
Passing time step from ODE solver (ode23tb) to ODE function
The evaluation of 'blah' depends on all previous steps taken. That sounds like you don't have an ordinary differential equati...

5 days ago | 2

Answered
how matlab stores graphics objects?
The Bytes column of the output of whos does not tell the "truth, whole truth, and nothing but the truth" for certain situations....

5 days ago | 0

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Answered
Array indices must be positive or logical values
for i = 1:N j = i+0.5 y(i+1) = y(i) + h*f(x(j), y(j)); end There's no such thing as the 1.5th element of either x or y ...

5 days ago | 0

Answered
Standalone application: console blocks program
You may be encountering the behavior described in this Stack Overflow post.

5 days ago | 1

Answered
How to increase axis of stem plots
Use the axis function to set the limits.

5 days ago | 0

Answered
what kind of license do I need?
I advise you to contact the Sales department and work with them to determine the license configuration that will best meet your ...

5 days ago | 0

Answered
Random generator with constraints
A = rand(6, 4); [~, ind] = sort(A, 2)

5 days ago | 1