Community Profile

photo

Steven Lord


MathWorks

3.363 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.

Steven Lord's Badges

  • 24 Month Streak
  • Ace
  • Revival Level 3
  • Thankful Level 3
  • Knowledgeable Level 4
  • First Answer
  • Scavenger Finisher
  • Solver

View details...

Contributions in
View by

Answered
Extreme points finding from set
I suspect some combination of islocalmin, islocalmax, and/or ischange will identify the points you've called out with + markers ...

alrededor de 15 horas ago | 0

Answered
fill a polygon with a hole
Consider creating and plotting a polyshape. You will receive a warning but depending on how you've generated your data you may b...

alrededor de 16 horas ago | 0

Answered
How to unfix the seed with Matlab engine?
Every time you call matlab.engine.start_matlab you're starting a new MATLAB process. See this documentation page for how to "Gen...

alrededor de 16 horas ago | 0

| accepted

Answered
How to generate -1, 0 and 1?
If you want to map ranges of values in your original data to the values -1, 0, and 1 you could discretize your data. Use the syn...

alrededor de 17 horas ago | 0

Answered
How to control the randomness of algorithm
See the three topics in the "Control Random Number Generation" section on this documentation page.

alrededor de 20 horas ago | 0

Answered
round off problem in matlab
Based on that display I suspect one or both of the variables zcdOut or slope_count are stored in an integer class. When you comb...

alrededor de 20 horas ago | 0

Answered
HOW to download 2019b iso disc image
As per this message if you are a licensed end user you will need to ask your license administrator to download it.

alrededor de 20 horas ago | 0

Answered
I cannot open the following tutorial in R2018a version. Photovoltaic Thermal (PV/T) Hybrid Solar Panel
This example was introduced in Simscape Electrical in release R2019b, according to the Release Notes. It doesn't exist in earlie...

alrededor de 20 horas ago | 0

Answered
Banded Matrix Solver in Matlab
Since you've tagged this question with "sparse", try just using the backslash operator. The flowchart on that documentation page...

1 día ago | 1

| accepted

Answered
accuracy problems in uint64 numbers
It really depends on how you performed your computations. Let's take a somewhat large number, 3^40. xDouble = 3^40; xUint64 = ...

1 día ago | 0

Answered
PLOT THE GRAPH OF VECTOR FUNCTIONS
If you have a picture in your mind of how you want the graph to look, open the Plots tab in the Toolstrip and click the triangle...

2 días ago | 0

Answered
Convert table and obtain column values
Use ismissing to locate the missing values (you can tell ismissing what it should consider as a missing value) then use the logi...

2 días ago | 0

Answered
What is the best way to insure that all of my functions are using the same constant values?
You could define a class with Constant properties. classdef myconstants properties(Constant) g = 9.8; g_...

3 días ago | 4

| accepted

Answered
can I return more than one argument in the "odefun" when called from ode45
What you've described sounds not like an ordinary differential equation (ODE) but like a delay differential equation (DDE). This...

3 días ago | 1

Answered
Find specific date/time from a series of datenums
If you're going to be doing a lot of processing of this data based on the times, consider turning your column of date numbers in...

3 días ago | 0

Answered
Undefined function or variable 'ranova'
The only ranova function I see in the documentation is this one. In order to call this function, the first input must be a Repea...

3 días ago | 0

| accepted

Answered
Write class methods outside the class file
Rather than defining the class methods in the classdef file to call a separate function, I'd just define them in a separate file...

4 días ago | 1

| accepted

Answered
Event function with multiple events
When you define your options structure with: option2 = odeset('Events', @comp); the ODE solver will call your Events function ...

4 días ago | 0

| accepted

Answered
Extract Variable/column with variable name from table
In what form do you want the extracted variables to be stored? A = magic(4); T = array2table(A) % Variable names A1 through A4...

4 días ago | 0

| accepted

Answered
Is there a way that we can identify the output of the figures that fall within the assigned range?
Use the discretize function.

6 días ago | 0

| accepted

Answered
Roots function is solving eigth order polynomial equation as fifth order.
Specify the 'All' option in your call to coeffs to return all the coefficients, even those that are 0.

6 días ago | 0

| accepted

Answered
Separate out every fourth element of a Vector
If by " so you have to make it clear that this is not the intention." you mean you don't want to delete every fourth element but...

7 días ago | 0

Answered
Create variable from an excel entry
Are you required to store this data in an Excel spreadsheet? I'd prefer storing this in a plain text file. Plot.Shift=20; Plot...

7 días ago | 0

Answered
how to catch when a figure was minimized
Make the figure window 'fullscreen'? f = figure('WindowState', 'fullscreen');

8 días ago | 0

Answered
Comparing Duration Arrays is time consuming - How to improve my script?
So you want to extract only those subset of rows of your data that fall into a certain time span? If so, and if you choose to st...

8 días ago | 0

Answered
Changing data from long form to short form
Participant_ID = [1; 1; 1; 2; 2; 2]; Trial = [1; 2; 3; 1; 2; 3]; RT = [342; 346; 534; 242; 131; 531]; t = table(Participant...

8 días ago | 2

Answered
Count how many elements are present inside arrays
V= [1 2 3 4 7 8 9 10 11 12 14 16 17]; P = [1 2 3 4 7 8 9 10 11 12 14 16 17 2 7 9 11 12 3 1 10]; F = [1 2 3 4 7 9 10 11 12 14 ...

8 días ago | 0

Answered
Binning a column vector to certain values (includes negative values)
The left edge of your first bin should be less than than the first value you want included in that bin. Right now, -0.2 doesn't ...

8 días ago | 0

Answered
How can I prealloate a comlex-valued matrix?
I would probably use the 'like' syntax for the zeros function. A = zeros(10000, 500, 'like', 1i);

8 días ago | 2

| accepted

Load more