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Is it possible to truncate a vector to form one of lower dimension?

You have two choices. First, you can extract the elements you want. Or you can delete the elements you wnat to drop. For example...

Is it possible to truncate a vector to form one of lower dimension?

You have two choices. First, you can extract the elements you want. Or you can delete the elements you wnat to drop. For example...

12 Tage vor | 1

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Most efficient way to put vector on the off-diagonal of the blocks of a block matrix

The most efficient way? SPDIAGS. help spdiags For example, to create a 6x6 sparse matrix, with an upper and lower diagonal ele...

Most efficient way to put vector on the off-diagonal of the blocks of a block matrix

The most efficient way? SPDIAGS. help spdiags For example, to create a 6x6 sparse matrix, with an upper and lower diagonal ele...

14 Tage vor | 0

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xy+y^5+3=0 My input is real x, from this implicit equation y will have both real and imag values for each x I want to plot a 3 D plot where z will represent imag y. Pleasehelp

Simple enough. Just do exactly what you asked. Remember the roots of a 5th degree polynomial will in general have no algebraic s...

xy+y^5+3=0 My input is real x, from this implicit equation y will have both real and imag values for each x I want to plot a 3 D plot where z will represent imag y. Pleasehelp

Simple enough. Just do exactly what you asked. Remember the roots of a 5th degree polynomial will in general have no algebraic s...

14 Tage vor | 0

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How do I fit two data sets to each other?

This is a classic problem of calibration. You have two curves, one of which must be shifted (translated) to the other. In some c...

How do I fit two data sets to each other?

This is a classic problem of calibration. You have two curves, one of which must be shifted (translated) to the other. In some c...

15 Tage vor | 1

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Pick a value with some probability

Please stop asking the same question. There is NO way to know what distribution any set of data comes from. You can use tools to...

Pick a value with some probability

Please stop asking the same question. There is NO way to know what distribution any set of data comes from. You can use tools to...

15 Tage vor | 0

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Why is the calculated Rsquare different between the embedded fit function and the EzyFit function (from File Exchange)?

Do you understand that R^2 is not valid, when computed for a model with no constant term? Instead, I recall there are variations...

Why is the calculated Rsquare different between the embedded fit function and the EzyFit function (from File Exchange)?

Do you understand that R^2 is not valid, when computed for a model with no constant term? Instead, I recall there are variations...

16 Tage vor | 1

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I wanna implement this function, but it says there is an syntax error..

What langiuage are you using when you end a function with the statement endfunction? Not MATLAB. As well, IF you had posted the...

I wanna implement this function, but it says there is an syntax error..

What langiuage are you using when you end a function with the statement endfunction? Not MATLAB. As well, IF you had posted the...

16 Tage vor | 0

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non-numerical answer for solving complex non-linear equation

I think you do not understand how variables work in MATLAB. Variables are dynamically assigned. When you assign them as you have...

non-numerical answer for solving complex non-linear equation

I think you do not understand how variables work in MATLAB. Variables are dynamically assigned. When you assign them as you have...

18 Tage vor | 0

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Can I use my student license for and at work?

I would guess the answer is technically no. But it is arguable either way as long as you remain a student, IF when you are on co...

Can I use my student license for and at work?

I would guess the answer is technically no. But it is arguable either way as long as you remain a student, IF when you are on co...

19 Tage vor | 1

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A single precision matrix multiplication problem

Why are you confused? NEVER trust the least significant bits of a floating point number. The numbers in a are singles. So the l...

A single precision matrix multiplication problem

Why are you confused? NEVER trust the least significant bits of a floating point number. The numbers in a are singles. So the l...

19 Tage vor | 3

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I am stuck in making the pentadiagonal matrix A

This sort of thing is a BAD idea: A = A+spdiags(s_vec, 0, (nx+1)*(ny+1), (nx+1)*(ny+1)); % Add s to the main diagonal of A XX_...

I am stuck in making the pentadiagonal matrix A

This sort of thing is a BAD idea: A = A+spdiags(s_vec, 0, (nx+1)*(ny+1), (nx+1)*(ny+1)); % Add s to the main diagonal of A XX_...

20 Tage vor | 0

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Find the derivative of a spline curve obtained using cscvn

No. There is no simple "function" of a spline. It is a mess of coefficients that by themselves are fairly meaningless to those w...

Find the derivative of a spline curve obtained using cscvn

No. There is no simple "function" of a spline. It is a mess of coefficients that by themselves are fairly meaningless to those w...

21 Tage vor | 0

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Fitting powerlaw between two points

Given two points exactly, thus: yx = [0.047 100; 0.0382 0.1933]; y1 = yx(:,1); x1 = yx(:,2); You want the power law cur...

Fitting powerlaw between two points

Given two points exactly, thus: yx = [0.047 100; 0.0382 0.1933]; y1 = yx(:,1); x1 = yx(:,2); You want the power law cur...

21 Tage vor | 0

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How to combine the trapezoidal rule with interpolation in ode23t function

A FREE interpolant is one where the nodes are not fixed in advance. For example, suppose I choose to interpolate sin(x), on th...

How to combine the trapezoidal rule with interpolation in ode23t function

A FREE interpolant is one where the nodes are not fixed in advance. For example, suppose I choose to interpolate sin(x), on th...

21 Tage vor | 0

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How to get the combination "nCk", if either n or k is a variable.

if x(3) is NOT an integer, then what do you expect? If x(3) is NOT at least as large as d, then what do you expect? In either...

How to get the combination "nCk", if either n or k is a variable.

if x(3) is NOT an integer, then what do you expect? If x(3) is NOT at least as large as d, then what do you expect? In either...

21 Tage vor | 0

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Fitting 3D data into a function

The curve fitting toolbox does not fit models with more than 2 independent variables. You can use my polyfitn tool, found on th...

Fitting 3D data into a function

The curve fitting toolbox does not fit models with more than 2 independent variables. You can use my polyfitn tool, found on th...

22 Tage vor | 1

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How to solve exponential variables

The problem is, you have been trying to SOLVE them. More approproately, you want to use a tool that will FIT your model to the...

How to solve exponential variables

The problem is, you have been trying to SOLVE them. More approproately, you want to use a tool that will FIT your model to the...

22 Tage vor | 0

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Laguerre polynomials of large degree.

If you are using double precision, then OF COURSE high order polynomials of any form in MATLAB should not be trusted!!!! At leas...

Laguerre polynomials of large degree.

If you are using double precision, then OF COURSE high order polynomials of any form in MATLAB should not be trusted!!!! At leas...

26 Tage vor | 1

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Shifting an array without circshift

Nobody can know what you did wrong. circshift DOES work. I'm not even sure what you would have done that would cause an error. T...

Shifting an array without circshift

Nobody can know what you did wrong. circshift DOES work. I'm not even sure what you would have done that would cause an error. T...

26 Tage vor | 0

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trying to solve two non-linear simultaneous equations but I had an error figuring out my two unknowns (X(1) &x(2)) , can anyone pls help?

ARGH. Why would you post a picture of your code? And at that, only a partial picture? Even if I try to show why your code fails,...

trying to solve two non-linear simultaneous equations but I had an error figuring out my two unknowns (X(1) &x(2)) , can anyone pls help?

ARGH. Why would you post a picture of your code? And at that, only a partial picture? Even if I try to show why your code fails,...

28 Tage vor | 0

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How to determine concavity point?

You give no data, so I'll need to make some up for an example. x = linspace(-30,30,500); y = cumsum((atan(x - 10)/2 + 1)); pl...

How to determine concavity point?

You give no data, so I'll need to make some up for an example. x = linspace(-30,30,500); y = cumsum((atan(x - 10)/2 + 1)); pl...

29 Tage vor | 0

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What to be chosen c so that all elements of matrix B will be a round number. B=A.c; where A is the matrix of non integers.

You want to find some scalar value c, such that for some given vector A, you want the product A*c = B to be purely a vecto...

What to be chosen c so that all elements of matrix B will be a round number. B=A.c; where A is the matrix of non integers.

You want to find some scalar value c, such that for some given vector A, you want the product A*c = B to be purely a vecto...

etwa ein Monat vor | 2

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How can i simulate a generic poisson process?

Not sure how you built the vector. Is it a Poisson process? Could be. :) As I recall, if you have exponential inter-rarrival tim...

How can i simulate a generic poisson process?

Not sure how you built the vector. Is it a Poisson process? Could be. :) As I recall, if you have exponential inter-rarrival tim...

etwa ein Monat vor | 1

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mvncdf gives different results before and after the variable is standardised

No answer yet? The distinction as I see it is a subtle one. And had your covariance matrix been a diagonal one, then I expect it...

mvncdf gives different results before and after the variable is standardised

No answer yet? The distinction as I see it is a subtle one. And had your covariance matrix been a diagonal one, then I expect it...

etwa ein Monat vor | 0

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Delete a plane (2d) within a 3d matrix

Sometimes it is simpler to take what you want, than it is to delete what you don't want. Here is a matrix: A = rand(256,256,256...

Delete a plane (2d) within a 3d matrix

Sometimes it is simpler to take what you want, than it is to delete what you don't want. Here is a matrix: A = rand(256,256,256...

etwa ein Monat vor | 0

| akzeptiert

Beantwortet

How do I find the (right) null space of a matrix?

Easy. A = rand(5,2)*rand(2,3) A has rank 2. Arnull = null(A) A*Arnull It kills A, which is what the right nullspace would d...

How do I find the (right) null space of a matrix?

Easy. A = rand(5,2)*rand(2,3) A has rank 2. Arnull = null(A) A*Arnull It kills A, which is what the right nullspace would d...

etwa ein Monat vor | 0

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asking for a polynomial expression in an input

Can you type in a polynomial? Why not? You type it anyway. Just use input, which can return the result as a string. Or, use a di...

asking for a polynomial expression in an input

Can you type in a polynomial? Why not? You type it anyway. Just use input, which can return the result as a string. Or, use a di...

etwa ein Monat vor | 0

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How do i keep track of eigenvalue on pzmap for a pariticular system matrix A containing a variable D?

You can use the tool I wrote, eigenshuffle. It sorts the eigenvalues in as consistent an order as possible, by assuming the corr...

How do i keep track of eigenvalue on pzmap for a pariticular system matrix A containing a variable D?

You can use the tool I wrote, eigenshuffle. It sorts the eigenvalues in as consistent an order as possible, by assuming the corr...

etwa ein Monat vor | 0

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Error using "*" in my equation, assumes I am trying to do matrix multiplication.

Even though you are not using matrices, does not mean that linear algebra could not be intended. MATLAB does not know what you a...

Error using "*" in my equation, assumes I am trying to do matrix multiplication.

Even though you are not using matrices, does not mean that linear algebra could not be intended. MATLAB does not know what you a...

etwa ein Monat vor | 0

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Finding the turning points

If all you will use are the 100 coarsely sampled points you are plotting, then min and max will do what you want. Look at the se...

Finding the turning points

If all you will use are the 100 coarsely sampled points you are plotting, then min and max will do what you want. Look at the se...

etwa ein Monat vor | 0