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

Out of memory (infinite recursion) running a stochastic collocation

[mean, stdev] = Stochastic_Collocation(x,nomforce); You call your function inside itself, which causes your function to cal...

Out of memory (infinite recursion) running a stochastic collocation

[mean, stdev] = Stochastic_Collocation(x,nomforce); You call your function inside itself, which causes your function to cal...

14 hours ago | 1

| accepted

Answered

Issue with atan2(.)

The atan2 function included in MATLAB requires exactly two input arguments. Therefore you're likely calling a different atan2.m ...

Issue with atan2(.)

The atan2 function included in MATLAB requires exactly two input arguments. Therefore you're likely calling a different atan2.m ...

15 hours ago | 0

Answered

Pre-allocating memory for a while loop

I'm running a code that is based on a while loop to similate a chemical process. It simulates an added amount of species each se...

Pre-allocating memory for a while loop

I'm running a code that is based on a while loop to similate a chemical process. It simulates an added amount of species each se...

23 hours ago | 0

Answered

Is there any option to use boxlabelDatastore function in Matlab 2017b?

This function was introduced in Computer Vision Toolbox in release R2019b according to the note at the end of its documentation ...

Is there any option to use boxlabelDatastore function in Matlab 2017b?

This function was introduced in Computer Vision Toolbox in release R2019b according to the note at the end of its documentation ...

23 hours ago | 0

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Answered

Wrong left and right assignment error

for n= 1:1:100 l(n) = n.*(a.*b.*c); When you execute that second line of code, n is a scalar (size 1-by-1.) The variables ...

Wrong left and right assignment error

for n= 1:1:100 l(n) = n.*(a.*b.*c); When you execute that second line of code, n is a scalar (size 1-by-1.) The variables ...

23 hours ago | 0

Answered

wlan toolbox is incompleted

There's a note at the end of the documentation page that states this function was introduced in release R2019a. If you're using ...

wlan toolbox is incompleted

There's a note at the end of the documentation page that states this function was introduced in release R2019a. If you're using ...

3 days ago | 0

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...

4 days ago | 0

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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...

5 days ago | 0

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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.

5 days 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...

5 days ago | 1

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 ...

5 days ago | 0

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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...

5 days 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...

5 days 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, ...

6 days 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-...

6 days 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...

6 days 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)

8 days ago | 0

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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...

8 days 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 ...

8 days 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...

8 days 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 ...

8 days 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...

8 days ago | 1

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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...

8 days 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...

9 days 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...

10 days ago | 0

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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...

10 days 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...

10 days 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 = ...

10 days 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...

10 days ago | 1

| accepted