Steven Lord
MathWorks
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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How do I reliably extract the date from a string, given that it could be in a number formats and positions?
You have ambiguity in your dates that cannot be automatically determined. s = '368446-SN.24260046-12.08.2026' Does this repres...
How do I reliably extract the date from a string, given that it could be in a number formats and positions?
You have ambiguity in your dates that cannot be automatically determined. s = '368446-SN.24260046-12.08.2026' Does this repres...
3日 前 | 0
回答済み
Plotting Symbolic 3x3 System of Equations
%Define symbolic variables and equations syms x y w eq1 = 2*x -y + w == -5; eq2 = y + 3*w == 7; eq3 = w==2; equations = [e...
Plotting Symbolic 3x3 System of Equations
%Define symbolic variables and equations syms x y w eq1 = 2*x -y + w == -5; eq2 = y + 3*w == 7; eq3 = w==2; equations = [e...
3日 前 | 0
回答済み
Explicit conversion to uint64 results in Conversion failed! error
This is Bug Report 3014238, reported fixed in release R2020b. Using the u64 suffix or wrapping the constant in square brackets a...
Explicit conversion to uint64 results in Conversion failed! error
This is Bug Report 3014238, reported fixed in release R2020b. Using the u64 suffix or wrapping the constant in square brackets a...
19日 前 | 0
| 採用済み
回答済み
how can I count the number of elements on a vector?
There are several questions being asked by the original poster. As of release R2025a to answer the question "How many unique ele...
how can I count the number of elements on a vector?
There are several questions being asked by the original poster. As of release R2025a to answer the question "How many unique ele...
20日 前 | 0
回答済み
"localAgentFunctionsForMemUsage" could not be recognized
My guess is that you've made a copy of one of the examples from the documentation to use as a starting point for your code, but ...
"localAgentFunctionsForMemUsage" could not be recognized
My guess is that you've made a copy of one of the examples from the documentation to use as a starting point for your code, but ...
約1ヶ月 前 | 0
回答済み
How to obtain the activation key for the R2026a matlab
If you're trying to use your company or educational institution's license, ask whoever maintains the organization's software lic...
How to obtain the activation key for the R2026a matlab
If you're trying to use your company or educational institution's license, ask whoever maintains the organization's software lic...
約2ヶ月 前 | 0
回答済み
why does factor(1) return 1? shouldn't it return null?
Technically, yes. If you want prod(factor(x)) to return x and the output of factor to only include prime numbers, having factor(...
why does factor(1) return 1? shouldn't it return null?
Technically, yes. If you want prod(factor(x)) to return x and the output of factor to only include prime numbers, having factor(...
約2ヶ月 前 | 0
回答済み
Why does rng('shuffle') always return a Seed of 0 when first run?
This is the correct and expected behavior. When called with an input argument and an output argument, the rng function returns ...
Why does rng('shuffle') always return a Seed of 0 when first run?
This is the correct and expected behavior. When called with an input argument and an output argument, the rng function returns ...
約2ヶ月 前 | 0
| 採用済み
回答済み
Taking part in the boundary calculation from the function
So you want to ensure that x(3) <= x(1)+x(2)-0.0001? That's not a bound, that's a linear constraint. Write it as -x(1)-x(2)+x(3...
Taking part in the boundary calculation from the function
So you want to ensure that x(3) <= x(1)+x(2)-0.0001? That's not a bound, that's a linear constraint. Write it as -x(1)-x(2)+x(3...
約2ヶ月 前 | 1
| 採用済み
回答済み
using imaginary notation gives an error (-J)
If by "carrots" you mean an orange squiggle underline in the Editor representing a Code Analyzer warning, and if just the "q1" s...
using imaginary notation gives an error (-J)
If by "carrots" you mean an orange squiggle underline in the Editor representing a Code Analyzer warning, and if just the "q1" s...
2ヶ月 前 | 0
| 採用済み
回答済み
MATLAB Randomly Changes Values in Array to Scientific Notation
You may think the values in the array are integer values, but they're not. They're just barely different from an integer value. ...
MATLAB Randomly Changes Values in Array to Scientific Notation
You may think the values in the array are integer values, but they're not. They're just barely different from an integer value. ...
2ヶ月 前 | 2
回答済み
Teaching Matlab to a visually impaired person
I have not gone through these myself, but I suspect that the MathWorks training courses are accessible for visually impaired per...
Teaching Matlab to a visually impaired person
I have not gone through these myself, but I suspect that the MathWorks training courses are accessible for visually impaired per...
2ヶ月 前 | 1
回答済み
How to calculate the average value of a vector in MATLAB?
If you're not sure what function to use or if there is a function to use for a particular task, I recommend searching the MATLAB...
How to calculate the average value of a vector in MATLAB?
If you're not sure what function to use or if there is a function to use for a particular task, I recommend searching the MATLAB...
2ヶ月 前 | 0
回答済み
Can I solve a symetric system using only the lower triangular portion of the matrix?
The backslash operator (mldivide, \) does not have a way to specify that the coefficient matrix you pass to it actually only rep...
Can I solve a symetric system using only the lower triangular portion of the matrix?
The backslash operator (mldivide, \) does not have a way to specify that the coefficient matrix you pass to it actually only rep...
2ヶ月 前 | 0
| 採用済み
回答済み
How to set a tolerance?
You indicated you've resolved your problem, but depending on your exact goal some tools that might help you with problems like t...
How to set a tolerance?
You indicated you've resolved your problem, but depending on your exact goal some tools that might help you with problems like t...
3ヶ月 前 | 0
回答済み
Just a question: Will there be a 2026 version for macOS Intel?
From the current System Requirements page for Mac: "Note: MATLAB is no longer available for Macs with Intel processors" The Pla...
Just a question: Will there be a 2026 version for macOS Intel?
From the current System Requirements page for Mac: "Note: MATLAB is no longer available for Macs with Intel processors" The Pla...
3ヶ月 前 | 1
回答済み
Solving diffeerntial equations numerically
If you use the ode object you can call its solve method to return the solution at specified times. If you're using a specific O...
Solving diffeerntial equations numerically
If you use the ode object you can call its solve method to return the solution at specified times. If you're using a specific O...
3ヶ月 前 | 0
回答済み
How can I dynamically create and configure a subclass of an abstract class from a file or script in one step in MATLAB?
As written, each time you add a new type of Vehicle you need to modify Garage to be able to handle that new type of vehicle. Thi...
How can I dynamically create and configure a subclass of an abstract class from a file or script in one step in MATLAB?
As written, each time you add a new type of Vehicle you need to modify Garage to be able to handle that new type of vehicle. Thi...
4ヶ月 前 | 0
回答済み
Access to downloads for install
If you already have a license but need information on where/how to download the software to be installed, please contact Custome...
Access to downloads for install
If you already have a license but need information on where/how to download the software to be installed, please contact Custome...
4ヶ月 前 | 0
回答済み
How to find a function in the path - securely?
The complexity explodes, such that a simple task like searching a function file needs a pile of exceptions and indirections. S...
How to find a function in the path - securely?
The complexity explodes, such that a simple task like searching a function file needs a pile of exceptions and indirections. S...
4ヶ月 前 | 1
回答済み
computation of symbolic terms and error analysis
You indicated you've already found the solution (the expression you're trying to convert to double still has symbolic variables ...
computation of symbolic terms and error analysis
You indicated you've already found the solution (the expression you're trying to convert to double still has symbolic variables ...
4ヶ月 前 | 0
回答済み
Can you get matlab to add a really small number to a big number and retain precision
p = -1e17 + sqrt(1e34 + 1e18) p is in fact exactly 0 if you do the calculation in double precision. p == 0 % true Why didn't ...
Can you get matlab to add a really small number to a big number and retain precision
p = -1e17 + sqrt(1e34 + 1e18) p is in fact exactly 0 if you do the calculation in double precision. p == 0 % true Why didn't ...
4ヶ月 前 | 3
| 採用済み
回答済み
trainnet function - randomness and repeatability
What happens when you reset the state or seed of the random number generator before each attempt to train the network? Let's cho...
trainnet function - randomness and repeatability
What happens when you reset the state or seed of the random number generator before each attempt to train the network? Let's cho...
4ヶ月 前 | 0
| 採用済み
回答済み
Trying to solve for a number of variables in a matrix. Getting a structfun error.
Let's look at what solution is after the call to solve. I just added in a few semicolons to suppress some of the output. E = 10...
Trying to solve for a number of variables in a matrix. Getting a structfun error.
Let's look at what solution is after the call to solve. I just added in a few semicolons to suppress some of the output. E = 10...
5ヶ月 前 | 0
回答済み
Financial Toolbox installed but bndprice function not found
According to the output of ver that you posted, you're using MATLAB Online (basic). According to the FAQ on the page describing ...
Financial Toolbox installed but bndprice function not found
According to the output of ver that you posted, you're using MATLAB Online (basic). According to the FAQ on the page describing ...
5ヶ月 前 | 0
回答済み
Reading a string & sorting it into usable variables
Let's take a sample string. S = "Layup: [45/-45/0/90/90/0/-45/45]"; Get the text after the leading [ S2 = extractAfter(S, "["...
Reading a string & sorting it into usable variables
Let's take a sample string. S = "Layup: [45/-45/0/90/90/0/-45/45]"; Get the text after the leading [ S2 = extractAfter(S, "["...
5ヶ月 前 | 0
回答済み
I have downloaded this package, but can not seem to use the "readDistance' command.
Searching the documentation for functions named readDistance, I found two hits on the first page. The first one requires the MA...
I have downloaded this package, but can not seem to use the "readDistance' command.
Searching the documentation for functions named readDistance, I found two hits on the first page. The first one requires the MA...
5ヶ月 前 | 1
回答済み
Dialog box Unable to resolve the name 'matlab.io.internal.xlsreadSupportedExtensions' error prevents me from opening a file
The fact that the error occurs on line 5 of pad (which in my installation of release R2025b is completely blank) in a call to re...
Dialog box Unable to resolve the name 'matlab.io.internal.xlsreadSupportedExtensions' error prevents me from opening a file
The fact that the error occurs on line 5 of pad (which in my installation of release R2025b is completely blank) in a call to re...
5ヶ月 前 | 0
回答済み
MATLAB standalone App Dynamic Class
From the documentation "MATLAB Runtime only works on MATLAB code that was encrypted when the deployable archive was built. Any f...
MATLAB standalone App Dynamic Class
From the documentation "MATLAB Runtime only works on MATLAB code that was encrypted when the deployable archive was built. Any f...
5ヶ月 前 | 0
