Answered

can fzero be used to find the minimum ?

Do you have the optimization toolbox? To start you can begin with the fminbnd function. For example, say your function is g(...

can fzero be used to find the minimum ?

Do you have the optimization toolbox? To start you can begin with the fminbnd function. For example, say your function is g(...

8 years ago | 0

| accepted

Answered

How to sum part of a column?

If your matrix is called A, then rows 1 and 2 in column 3 can be identified with the syntax A( 1:2, 3 ) So sum it using ...

How to sum part of a column?

If your matrix is called A, then rows 1 and 2 in column 3 can be identified with the syntax A( 1:2, 3 ) So sum it using ...

8 years ago | 0

| accepted

Answered

Save Variable in Command Window

You want to use the function |path| so don't create a new variable called |path|! Instead try this prompt = 'Enter the pat...

Save Variable in Command Window

You want to use the function |path| so don't create a new variable called |path|! Instead try this prompt = 'Enter the pat...

9 years ago | 2

Answered

starting MATLAB and not experienced in programming

Also check out the MathWorks' <http://www.mathworks.com/academia/student_center/tutorials/ free MATLAB tutorial>.

starting MATLAB and not experienced in programming

Also check out the MathWorks' <http://www.mathworks.com/academia/student_center/tutorials/ free MATLAB tutorial>.

9 years ago | 0

Answered

Fixed-size text that zooms/scales with a plot?

Here's a cute little function that does what you're looking for. function textWithZoomEffect % plot some original da...

Fixed-size text that zooms/scales with a plot?

Here's a cute little function that does what you're looking for. function textWithZoomEffect % plot some original da...

9 years ago | 1

| accepted

Answered

Dumb mistakes we make with MATLAB.

>> close al Error using close (line 111) Specified window does not exist. Dammit!

Dumb mistakes we make with MATLAB.

>> close al Error using close (line 111) Specified window does not exist. Dammit!

9 years ago | 0

Answered

solving linear equations using matrices in MATLAB

If you're trying to solve for U in the expression K*U = F, don't use linprog or solve... use mldivide (the backslash operator) ...

solving linear equations using matrices in MATLAB

If you're trying to solve for U in the expression K*U = F, don't use linprog or solve... use mldivide (the backslash operator) ...

9 years ago | 1

Answered

what does eigenvalues expres in the covariance matrix?

Long story short: The eigenvalues of the covariance matrix encode the variability of the data in an orthogonal basis that captur...

what does eigenvalues expres in the covariance matrix?

Long story short: The eigenvalues of the covariance matrix encode the variability of the data in an orthogonal basis that captur...

9 years ago | 3

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Answered

Small "toy rocket" - Simulation

You're super close... Just make one change to the height function so it looks like this one below: function [h] = heig...

Small "toy rocket" - Simulation

You're super close... Just make one change to the height function so it looks like this one below: function [h] = heig...

9 years ago | 1

| accepted

Answered

Contour Plot from Coordinates

I will assume you have three vectors: x, y, and z (where z represents pressure). For example x = rand(1,100); y = rand(...

Contour Plot from Coordinates

I will assume you have three vectors: x, y, and z (where z represents pressure). For example x = rand(1,100); y = rand(...

9 years ago | 1

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Answered

Anonymous functions and integration

Try r = integral (@(x)f(x)'*f(x), 0, 1, 'ArrayValued', true);

Anonymous functions and integration

Try r = integral (@(x)f(x)'*f(x), 0, 1, 'ArrayValued', true);

9 years ago | 1

| accepted

Answered

Create orthonormal basis from a given vector

So, given vector v = [a;b;c]; in R^3, it follows that any point (x,y,z) that satisifies a*x + b*y + c*z = 0 (i.e. a poin...

Create orthonormal basis from a given vector

So, given vector v = [a;b;c]; in R^3, it follows that any point (x,y,z) that satisifies a*x + b*y + c*z = 0 (i.e. a poin...

9 years ago | 7

Answered

How can I return the last value of a vector?

Try X(end) In general, if X is a m-by-n-by-p-by... You can use X(end,end,end,...) to access element in last r...

How can I return the last value of a vector?

Try X(end) In general, if X is a m-by-n-by-p-by... You can use X(end,end,end,...) to access element in last r...

9 years ago | 0

| accepted

Answered

How to color RED to the lower portion of the curve

Replace the plot(x,y) command with area(x,y,'FaceColor',[1 0 0])

How to color RED to the lower portion of the curve

Replace the plot(x,y) command with area(x,y,'FaceColor',[1 0 0])

9 years ago | 1

| accepted

Answered

Fincon Warning: undesired gradient requirement

The trust-region-reflective algorithm is the default option for fmincon. You can specify the solver by adding the name-value ...

Fincon Warning: undesired gradient requirement

The trust-region-reflective algorithm is the default option for fmincon. You can specify the solver by adding the name-value ...

9 years ago | 0

| accepted

Answered

Permute problem - unexpected Matlab operator

The first command is invalid. The second command will work - and is what you want - once you remove the extra > at the beginn...

Permute problem - unexpected Matlab operator

The first command is invalid. The second command will work - and is what you want - once you remove the extra > at the beginn...

9 years ago | 1

| accepted

Answered

How to get the positive root of the cubic a*x^3+3*b*x^2+3*c*x+d=0

You can try b = .1:.1:2; a = 1; c = b+2; d = -3; posR = zeros(1,length(b)); for i = 1:length(b) r...

How to get the positive root of the cubic a*x^3+3*b*x^2+3*c*x+d=0

You can try b = .1:.1:2; a = 1; c = b+2; d = -3; posR = zeros(1,length(b)); for i = 1:length(b) r...

9 years ago | 0

| accepted

Answered

I want to show intersection of these two spheres. How should I do it?

The spheres you describe have equations 1.) x^2 + y^2 + z^2 = 1 2.) (x-0.25)^2 + (y+1/5)^2 + (z-0.1)^2 = 1 Since equati...

I want to show intersection of these two spheres. How should I do it?

The spheres you describe have equations 1.) x^2 + y^2 + z^2 = 1 2.) (x-0.25)^2 + (y+1/5)^2 + (z-0.1)^2 = 1 Since equati...

9 years ago | 0

| accepted

Answered

how to get SNR for 2 images

You'll get different answers, depending on who you're talking to. I would suggest using snr = 20*log(norm(X0,'fro')/no...

how to get SNR for 2 images

You'll get different answers, depending on who you're talking to. I would suggest using snr = 20*log(norm(X0,'fro')/no...

9 years ago | 0

Answered

How can I construct a dataset array from data on an excel worksheet with an unknown number of rows

Just try d = dataset('XLSFile',yourFileName,'Sheet','mysheet')

How can I construct a dataset array from data on an excel worksheet with an unknown number of rows

Just try d = dataset('XLSFile',yourFileName,'Sheet','mysheet')

9 years ago | 0

Answered

Rotate co ordinates by a rotation matrix.

Is that 5 radians or 5 degrees you wish to rotate the points. If it's 5 degrees, I think you mean to have rot = [cosd(5),s...

Rotate co ordinates by a rotation matrix.

Is that 5 radians or 5 degrees you wish to rotate the points. If it's 5 degrees, I think you mean to have rot = [cosd(5),s...

9 years ago | 0

| accepted

Answered

using a 'for' loop to create a vector

You are parametrizing your for-loop using a vector of nonintegers, then trying to index into the variable x. I would instead pa...

using a 'for' loop to create a vector

You are parametrizing your for-loop using a vector of nonintegers, then trying to index into the variable x. I would instead pa...

9 years ago | 2

| accepted

Answered

"Not enough input arguments" error when integrating a function

You need to use a function handle... try integral(@fun,0,1)

"Not enough input arguments" error when integrating a function

You need to use a function handle... try integral(@fun,0,1)

9 years ago | 2

Answered

how to combine cells into a matrix

Given your out varialble, try out = fliplr([out{:}]) If you want to flip each row vector, then concatentate use out...

how to combine cells into a matrix

Given your out varialble, try out = fliplr([out{:}]) If you want to flip each row vector, then concatentate use out...

9 years ago | 1

| accepted

Answered

can anybody please tell me the use of 'val' function in this program.., it is not a valid function,yet the program can't be executed without using this,or by changing the function name.

The lines [fname path]=uigetfile('*.mat'); fname=strcat(path,fname); load(fname ); will load a .mat file into the sco...

can anybody please tell me the use of 'val' function in this program.., it is not a valid function,yet the program can't be executed without using this,or by changing the function name.

The lines [fname path]=uigetfile('*.mat'); fname=strcat(path,fname); load(fname ); will load a .mat file into the sco...

9 years ago | 0

| accepted

Answered

Advice on a few bottlenecks in my code

If you don't need the actual indices, you can omit the find command to save time. In particular, notice that the following code...

Advice on a few bottlenecks in my code

If you don't need the actual indices, you can omit the find command to save time. In particular, notice that the following code...

9 years ago | 0

Answered

Saving variables and figures uniquely when processing a sequence of files

try hgsave(['SummaryPlot',num2str(ii)]); notice the square brackets in order to concatenate 'SummaryPlot' and the outpu...

Saving variables and figures uniquely when processing a sequence of files

try hgsave(['SummaryPlot',num2str(ii)]); notice the square brackets in order to concatenate 'SummaryPlot' and the outpu...

9 years ago | 0

| accepted

Answered

Help with timing a pushbutton being pushed twice

Computing the time elapsed between two date vectors is nontrivial, I bet you're getting some weird behavior here. Try using the ...

Help with timing a pushbutton being pushed twice

Computing the time elapsed between two date vectors is nontrivial, I bet you're getting some weird behavior here. Try using the ...

9 years ago | 0

Answered

How can I resolve this problem using vertcat on matrices for daily files to create a single matrix for the whole year?

So, I'm guessing that newData2 is not a structure, in particular it is a double? Perhaps try fixing your code by replacing th...

How can I resolve this problem using vertcat on matrices for daily files to create a single matrix for the whole year?

So, I'm guessing that newData2 is not a structure, in particular it is a double? Perhaps try fixing your code by replacing th...

9 years ago | 0

Answered

how to create a matrix with variables in it?

The best answer to your question will likely depend on what you want to do with A. Sometimes, I find the following commands use...

how to create a matrix with variables in it?

The best answer to your question will likely depend on what you want to do with A. Sometimes, I find the following commands use...

9 years ago | 4