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

Working with table.

Do you need your data to be stored in a table or would a timetable be acceptable instead? Offhand I can't think of anything you ...

Working with table.

Do you need your data to be stored in a table or would a timetable be acceptable instead? Offhand I can't think of anything you ...

ongeveer 11 uur ago | 0

Answered

Undefined function 'eq' for input arguments of type 'timetable'.

For this particular application, I recommend using standardizeMissing.

Undefined function 'eq' for input arguments of type 'timetable'.

For this particular application, I recommend using standardizeMissing.

1 dag ago | 1

| accepted

Answered

How can I group a timetable in hours 0-24h

See the "Aggregate Timetable Data and Calculate Mean Values" example on the retime documentation page. While that uses a duratio...

How can I group a timetable in hours 0-24h

See the "Aggregate Timetable Data and Calculate Mean Values" example on the retime documentation page. While that uses a duratio...

1 dag ago | 0

Answered

I keep getting the message: Unbalanced or unexpected parenthesis or bracket. How would I fix it? I'm trying to solve for the maximum and minimum with a function and it's constraint.

T = [ ax ay subs(g,{x y},{ax ay}) subs(f,{x y}, {ax ay })({bx by}) ... subs(g,{x y},{bx by}) subs(f,{x y}{bx by})] This p...

I keep getting the message: Unbalanced or unexpected parenthesis or bracket. How would I fix it? I'm trying to solve for the maximum and minimum with a function and it's constraint.

T = [ ax ay subs(g,{x y},{ax ay}) subs(f,{x y}, {ax ay })({bx by}) ... subs(g,{x y},{bx by}) subs(f,{x y}{bx by})] This p...

2 dagen ago | 0

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Answered

I need help building a dynamically evolving matrix based on a polynomial of unknown or user inputted size.

Take a look at the vander function.

I need help building a dynamically evolving matrix based on a polynomial of unknown or user inputted size.

Take a look at the vander function.

2 dagen ago | 0

Answered

What is the meaning of 'simplify(n./d)?

The expression n./d divides each element of n by the corresponding element of d (with a few caveats to that if they're different...

What is the meaning of 'simplify(n./d)?

The expression n./d divides each element of n by the corresponding element of d (with a few caveats to that if they're different...

2 dagen ago | 0

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Answered

how to get matlab 2019b

The latest release as I type this is release R2019a. Release R2019b is not out yet. If you want to use release R2019a, check wi...

how to get matlab 2019b

The latest release as I type this is release R2019a. Release R2019b is not out yet. If you want to use release R2019a, check wi...

4 dagen ago | 0

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Answered

How can I extract values from a histogram (figure)?

If you only have access to the figure file, use openfig to open it in a figure window then use findobj to obtain the handle of t...

How can I extract values from a histogram (figure)?

If you only have access to the figure file, use openfig to open it in a figure window then use findobj to obtain the handle of t...

5 dagen ago | 0

Answered

Why doe the data extracted from excel sheet gets converted to scientific power ?

To change the way the data is displayed (which will not impact how it is stored) use the format function.

Why doe the data extracted from excel sheet gets converted to scientific power ?

To change the way the data is displayed (which will not impact how it is stored) use the format function.

5 dagen ago | 0

Answered

How can I force a non-trivial solution for a second order ODE

Your equation is x''=[ 9/4-(12/(5-3exp(2t)))exp(2t)] x(t) with initial conditions x'=x=0. You are a racecar at the starting line...

How can I force a non-trivial solution for a second order ODE

Your equation is x''=[ 9/4-(12/(5-3exp(2t)))exp(2t)] x(t) with initial conditions x'=x=0. You are a racecar at the starting line...

6 dagen ago | 0

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Answered

How can I average datetimes of my array?

Convert your table to a timetable using table2timetable. Once you have your timetable call retime on it.

How can I average datetimes of my array?

Convert your table to a timetable using table2timetable. Once you have your timetable call retime on it.

6 dagen ago | 0

Answered

row dimension of aeq is inconsistent with length of beq. Help me pls.

You passed the inputs into fmincon in the wrong order. From the documentation page, the syntax you're calling is: x = fmincon(f...

row dimension of aeq is inconsistent with length of beq. Help me pls.

You passed the inputs into fmincon in the wrong order. From the documentation page, the syntax you're calling is: x = fmincon(f...

6 dagen ago | 0

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Answered

Pan does not work

Run this command: which -all pan From the error message it sounds like you've created a Simulink model named pan that is takin...

Pan does not work

Run this command: which -all pan From the error message it sounds like you've created a Simulink model named pan that is takin...

6 dagen ago | 0

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Answered

how tocreate a new array that select the columns with a specific prefix in the header row

Read your data into a table array using readtable. Since I don't have your spreadsheet, I'll just create a sample table using th...

how tocreate a new array that select the columns with a specific prefix in the header row

Read your data into a table array using readtable. Since I don't have your spreadsheet, I'll just create a sample table using th...

7 dagen ago | 1

Answered

Re-hash the intrinsic Matlab plot function to accept a string as a y input?

You could turn your text data into a categorical array then plot with that categorical data as the Y input. colors = categorica...

Re-hash the intrinsic Matlab plot function to accept a string as a y input?

You could turn your text data into a categorical array then plot with that categorical data as the Y input. colors = categorica...

8 dagen ago | 1

Answered

I got "The expression to the left of the equals sign is not a valid target for an assignment."

Just eliminate that line from your code. The way you've defined x on the next line will make it complex since i is already defin...

I got "The expression to the left of the equals sign is not a valid target for an assignment."

Just eliminate that line from your code. The way you've defined x on the next line will make it complex since i is already defin...

8 dagen ago | 0

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Answered

Dynamic size differential equation system

There's no need for a loop here. Work on vectors. function dvhdt = myodefun(t, vh, alpha, optV, beta) % Compute N from the vh ...

Dynamic size differential equation system

There's no need for a loop here. Work on vectors. function dvhdt = myodefun(t, vh, alpha, optV, beta) % Compute N from the vh ...

8 dagen ago | 0

Answered

Blackjack Program -- Random Card Deal

Deal 4 cards from the deck at once. Give the dealer the first two and the player the next two. As written, your code can give t...

Blackjack Program -- Random Card Deal

Deal 4 cards from the deck at once. Give the dealer the first two and the player the next two. As written, your code can give t...

10 dagen ago | 0

Answered

symbolic variable multiplication with numerical matrix

When you perform that multiplication, Symbolic Math Toolbox converts your numbers into rational numbers rather than leaving them...

symbolic variable multiplication with numerical matrix

When you perform that multiplication, Symbolic Math Toolbox converts your numbers into rational numbers rather than leaving them...

10 dagen ago | 1

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Answered

Resetting individual properties to default values: 2018b

The most straighforward way is probably to define a Hidden, Constant property holding the default value. Since it's Hidden it wo...

Resetting individual properties to default values: 2018b

The most straighforward way is probably to define a Hidden, Constant property holding the default value. Since it's Hidden it wo...

11 dagen ago | 0

Answered

how to separate date and time into 6 tables 01/01/2014 0:10:00? (year,month,day,hours,minutes and second)

Use the datevec function.

how to separate date and time into 6 tables 01/01/2014 0:10:00? (year,month,day,hours,minutes and second)

Use the datevec function.

12 dagen ago | 0

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Answered

How mink functions is used in 2016a or is there any alternate of this function ?

As stated at the end of the documentation page for mink, this function was "Introduced in R2017b". It does not exist in release ...

How mink functions is used in 2016a or is there any alternate of this function ?

As stated at the end of the documentation page for mink, this function was "Introduced in R2017b". It does not exist in release ...

12 dagen ago | 0

Answered

syms wrong message, definition

syms creates an Inf value as part of its operation, and you've enabled an error breakpoint that causes MATLAB to enter debug mod...

syms wrong message, definition

syms creates an Inf value as part of its operation, and you've enabled an error breakpoint that causes MATLAB to enter debug mod...

13 dagen ago | 0

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Answered

suptitle in 2016a

If you are using release R2018b or later, I recommend using the sgtitle function instead of suptitle. subplot(2, 2, 1); plot(1...

suptitle in 2016a

If you are using release R2018b or later, I recommend using the sgtitle function instead of suptitle. subplot(2, 2, 1); plot(1...

13 dagen ago | 0

Answered

How can I create this 2D waterfall plot?

That's not a waterfall plot, at least not by my understanding. To me a waterfall plot looks like the picture shown on the waterf...

How can I create this 2D waterfall plot?

That's not a waterfall plot, at least not by my understanding. To me a waterfall plot looks like the picture shown on the waterf...

13 dagen ago | 0

Answered

How can I represent the mean in figure

You can 'center' your data using the normalize function. As for "represent the data in figure" do you mean you want to plot the...

How can I represent the mean in figure

You can 'center' your data using the normalize function. As for "represent the data in figure" do you mean you want to plot the...

13 dagen ago | 0

Answered

Access different property from set method in class

As long as the get method for the useGpu property doesn't try to set the smaps property (leading to an infinite loop) and as lon...

Access different property from set method in class

As long as the get method for the useGpu property doesn't try to set the smaps property (leading to an infinite loop) and as lon...

13 dagen ago | 0

| accepted

Answered

New to MATLAB, question about num2str

I recommend not using datetime as the name of your variable as it already has a meaning in MATLAB. If you want to use a datetime...

New to MATLAB, question about num2str

I recommend not using datetime as the name of your variable as it already has a meaning in MATLAB. If you want to use a datetime...

13 dagen ago | 1

Answered

realmax + 1 infinity?

If you handed Bill Gates or Scrooge McDuck a $1 bill, it doesn't change what he'll report for his net worth. A single dollar is ...

realmax + 1 infinity?

If you handed Bill Gates or Scrooge McDuck a $1 bill, it doesn't change what he'll report for his net worth. A single dollar is ...

13 dagen ago | 1