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.

Answered

Using now() in different time zones (or with daylight saving time)

If you want control over the time zone, you probably want to use datetime instead of now. N1 = datetime('now', 'TimeZone', 'loc...

Using now() in different time zones (or with daylight saving time)

If you want control over the time zone, you probably want to use datetime instead of now. N1 = datetime('now', 'TimeZone', 'loc...

environ 9 heures ago | 0

| accepted

Answered

How to override inherited methods?

You can't do what you asked. If you could, you could relax the property setting validation to the point where your subClass inst...

How to override inherited methods?

You can't do what you asked. If you could, you could relax the property setting validation to the point where your subClass inst...

1 jour ago | 0

| accepted

Answered

Why is format long providing a strange result?

I recommend using format longg instead of format long for this case.

Why is format long providing a strange result?

I recommend using format longg instead of format long for this case.

1 jour ago | 1

Answered

Set properties of child objects without synchronisation errors

Let's take a step back from the code for a second. Can you describe the design of your system for which this set of classes will...

Set properties of child objects without synchronisation errors

Let's take a step back from the code for a second. Can you describe the design of your system for which this set of classes will...

1 jour ago | 0

Answered

How to require a custom class type with addRequired?

You probably want to use addParameter instead of addRequired. If you're using release R2019b or later, consider using function ...

How to require a custom class type with addRequired?

You probably want to use addParameter instead of addRequired. If you're using release R2019b or later, consider using function ...

1 jour ago | 0

| accepted

Answered

Replacing <undefined> in categoricals or defining a default value

You could fillmissing to fill in the <undefined> entries, but if you want to leave them as missing data for future processing yo...

Replacing <undefined> in categoricals or defining a default value

You could fillmissing to fill in the <undefined> entries, but if you want to leave them as missing data for future processing yo...

1 jour ago | 0

Answered

How would I use Voronoi and/or Delaunay Triangulation methods for information on polygons

Why not just create a polyshape or an array of polyshape objects on which to operate? The NumRegions property gives you the numb...

How would I use Voronoi and/or Delaunay Triangulation methods for information on polygons

Why not just create a polyshape or an array of polyshape objects on which to operate? The NumRegions property gives you the numb...

1 jour ago | 0

Answered

How to solve a ODE that is a function of a cubic polynomial f(x) = 0?

This doesn't look like a system of ODEs. The presence of the variable d in the first set of curly braces threw me for a second, ...

How to solve a ODE that is a function of a cubic polynomial f(x) = 0?

This doesn't look like a system of ODEs. The presence of the variable d in the first set of curly braces threw me for a second, ...

2 jours ago | 0

Answered

Why is my for loop getting faster and faster?

This doesn't strike me as a bug. I suspect this is due to the execution engine introduced in release R2015b (which uses just-in-...

Why is my for loop getting faster and faster?

This doesn't strike me as a bug. I suspect this is due to the execution engine introduced in release R2015b (which uses just-in-...

2 jours ago | 0

| accepted

Answered

cannot modify plot axes as per documentation

Can you post the exact URL for the documentation page that says you can change the plot units by right-clicking, so we can see e...

cannot modify plot axes as per documentation

Can you post the exact URL for the documentation page that says you can change the plot units by right-clicking, so we can see e...

2 jours ago | 1

Answered

Find the data same week day one year ago.

You want the date exactly 52 calendar weeks ago? datetime('today')-calweeks(52)

Find the data same week day one year ago.

You want the date exactly 52 calendar weeks ago? datetime('today')-calweeks(52)

4 jours ago | 0

Answered

Derivative using datenum format vector

Use the minutes function to compute the difference between two elements of a datetime array (or two datetime arrays) in terms of...

Derivative using datenum format vector

Use the minutes function to compute the difference between two elements of a datetime array (or two datetime arrays) in terms of...

4 jours ago | 0

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Answered

ode45 for 4 DOF system - How to do with Matrices?

Is there a reason you're computing the inverse of the mass matrix and performing that multiplication instead of using odeset to ...

ode45 for 4 DOF system - How to do with Matrices?

Is there a reason you're computing the inverse of the mass matrix and performing that multiplication instead of using odeset to ...

4 jours ago | 0

Answered

simulering.m Line: 17 Column: 7 Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters.

for v_(size(t))=v_(size(t)-1)+f*i*F_red-Q_ud; That's not valid MATLAB syntax. It looks like you may be trying to create variabl...

simulering.m Line: 17 Column: 7 Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters.

for v_(size(t))=v_(size(t)-1)+f*i*F_red-Q_ud; That's not valid MATLAB syntax. It looks like you may be trying to create variabl...

4 jours ago | 0

Answered

Compare nearby elements in array

I think the islocalmax function, specifying both the dimension over which to operate and a 'ProminenceWindow', will do what you ...

Compare nearby elements in array

I think the islocalmax function, specifying both the dimension over which to operate and a 'ProminenceWindow', will do what you ...

4 jours ago | 0

Answered

Decision Branching Error in matlab onramp

That might be checking that the densities that are printed as text when doPlot is 0 exactly match the densities that would be pr...

Decision Branching Error in matlab onramp

That might be checking that the densities that are printed as text when doPlot is 0 exactly match the densities that would be pr...

5 jours ago | 1

| accepted

Answered

Solving Linear System of Equations with a Real Parameter

What do you know and what are you trying to find? Do you know the value of and you're trying to find the X values? If so, build...

Solving Linear System of Equations with a Real Parameter

What do you know and what are you trying to find? Do you know the value of and you're trying to find the X values? If so, build...

5 jours ago | 0

Answered

How to set title for matlab.graphics.primitive.Image ?

|image| objects don't have either a String or a Title property. The |axes| in which |image| objects are contained don't have a S...

How to set title for matlab.graphics.primitive.Image ?

|image| objects don't have either a String or a Title property. The |axes| in which |image| objects are contained don't have a S...

5 jours ago | 0

Answered

retime function not working

The variable tt is a |timetable|, but is MeanTempC? Nowhere in your code do you define it, but from the error I would guess it i...

retime function not working

The variable tt is a |timetable|, but is MeanTempC? Nowhere in your code do you define it, but from the error I would guess it i...

6 jours ago | 0

| accepted

Answered

Not sure why vector changes assignment when using ode45

[~,out3]=ode45(@thirdfun,t,y0,vector) This isn't the right way to pass a third input (beyond the two that |ode45| passes in...

Not sure why vector changes assignment when using ode45

[~,out3]=ode45(@thirdfun,t,y0,vector) This isn't the right way to pass a third input (beyond the two that |ode45| passes in...

6 jours ago | 0

| accepted

Answered

How do I generate a node graph of Matrix of resistors with a given pattern.

So you just want a rectangular grid of nodes with each connected to its neighbors above, below, left, and right except for nodes...

How do I generate a node graph of Matrix of resistors with a given pattern.

So you just want a rectangular grid of nodes with each connected to its neighbors above, below, left, and right except for nodes...

6 jours ago | 0

Answered

Splitting A String into variables

The code you posted already does this. >> a=input('enter calc: ','s') enter calc: 1+1 a = '1+1' >> a(1) ans = ...

Splitting A String into variables

The code you posted already does this. >> a=input('enter calc: ','s') enter calc: 1+1 a = '1+1' >> a(1) ans = ...

6 jours ago | 0

| accepted

Answered

Why this algorithm produces a relative error?

Walk through your code, line by line. How many times does MATLAB execute the body of your while loop? I think you want to itera...

Why this algorithm produces a relative error?

Walk through your code, line by line. How many times does MATLAB execute the body of your while loop? I think you want to itera...

6 jours ago | 0

Answered

How to write Continue Long Statements on Multiple Lines ?

Another way to do this, with a sufficiently recent release of MATLAB, is to join elements of a string array together with the re...

How to write Continue Long Statements on Multiple Lines ?

Another way to do this, with a sufficiently recent release of MATLAB, is to join elements of a string array together with the re...

6 jours ago | 1

| accepted

Answered

Element-wise Conditional Statements in Script

Use the max function with two inputs.

Element-wise Conditional Statements in Script

Use the max function with two inputs.

7 jours ago | 0

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Answered

Matlab Bingo Game card

randperm accepts a scalar (just one number) as its first input. You could generate a set of random numbers from 1 to 15 and use...

Matlab Bingo Game card

randperm accepts a scalar (just one number) as its first input. You could generate a set of random numbers from 1 to 15 and use...

9 jours ago | 0

| accepted

Answered

How do I get my function to form the derivative for Newton-Method

The diff function doesn't know how to operate on arbitrary function handles, including anonymous function handles. For functions...

How do I get my function to form the derivative for Newton-Method

The diff function doesn't know how to operate on arbitrary function handles, including anonymous function handles. For functions...

9 jours ago | 1

Answered

outputLimits function not found

Do you have Image Processing Toolbox installed? It was introduced in that toolbox in release R2013a, according to the documenta...

outputLimits function not found

Do you have Image Processing Toolbox installed? It was introduced in that toolbox in release R2013a, according to the documenta...

11 jours ago | 0

Answered

Error on official example "Classify Videos Using Deep Learning"

Which release are you using? The Release Notes for the most recent release (release R2019b as I type this) states that "AverageI...

Error on official example "Classify Videos Using Deep Learning"

Which release are you using? The Release Notes for the most recent release (release R2019b as I type this) states that "AverageI...

11 jours ago | 0