Answered

Help on trigonometric operations using syms variable.

You probably need to use rewrite. syms t4 S = sind(t4-90) S = sin((pi*(t4 - 90))/180) rewrite(expand(S),'sincos') ans ...

Help on trigonometric operations using syms variable.

You probably need to use rewrite. syms t4 S = sind(t4-90) S = sin((pi*(t4 - 90))/180) rewrite(expand(S),'sincos') ans ...

15 Tage ago | 2

| accepted

Answered

How to improve the accuracy of lu decomposition?

Sorry, but it is often the case that people are sloppy in their work. That is my expectation here. You gave us A and x_sol, but...

How to improve the accuracy of lu decomposition?

Sorry, but it is often the case that people are sloppy in their work. That is my expectation here. You gave us A and x_sol, but...

15 Tage ago | 0

Answered

how can I perform curve fitting for 3 degree exponential equation?

Fit will do it, sort of. You will need to pose an explicit model for the three terms. But please consider if you really can do ...

how can I perform curve fitting for 3 degree exponential equation?

Fit will do it, sort of. You will need to pose an explicit model for the three terms. But please consider if you really can do ...

16 Tage ago | 0

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Answered

which way to call function is better?

Neither way is "better". Both feel just a little clumsy, since I'm not sure why you feel the need to package the variables toget...

which way to call function is better?

Neither way is "better". Both feel just a little clumsy, since I'm not sure why you feel the need to package the variables toget...

16 Tage ago | 2

| accepted

Answered

Why is my newton method giving me a huge answer? What am i doing wrong?pls help

When you have a problem like this, plot the function. In fact, plot the function anyway! Next, it is a bad idea to use variable...

Why is my newton method giving me a huge answer? What am i doing wrong?pls help

When you have a problem like this, plot the function. In fact, plot the function anyway! Next, it is a bad idea to use variable...

17 Tage ago | 0

| accepted

Answered

Rolling Beta For Multiple x and y variables simultaneously

Is the x vector equally spaced? If so, then my movingslope code (found on the File Exchange) will do it trivially and efficientl...

Rolling Beta For Multiple x and y variables simultaneously

Is the x vector equally spaced? If so, then my movingslope code (found on the File Exchange) will do it trivially and efficientl...

17 Tage ago | 1

Answered

How do I plot an equation with an imaginary quantity?

Look at what you have. t=[0:0.01:10]; y=exp(-5*i*t); y(1:5) ans = 1 + 0i 0.99875 - 0.049979i ...

How do I plot an equation with an imaginary quantity?

Look at what you have. t=[0:0.01:10]; y=exp(-5*i*t); y(1:5) ans = 1 + 0i 0.99875 - 0.049979i ...

18 Tage ago | 0

Answered

Generate random Bistochastic matrix with zero diagonals

Hmm. I notice that the re-normalization trick offered by dpb sometimes seems to not converge well. That begs the question of wh...

Generate random Bistochastic matrix with zero diagonals

Hmm. I notice that the re-normalization trick offered by dpb sometimes seems to not converge well. That begs the question of wh...

18 Tage ago | 0

Answered

matalb convolution with memory

This is not a job for convolution, since h lies on both sides of the equality, with a lag on h. Use filter instead. You should...

matalb convolution with memory

This is not a job for convolution, since h lies on both sides of the equality, with a lag on h. Use filter instead. You should...

19 Tage ago | 0

Answered

Compare and modify random vector with evenly spaced vector

Again, learn to use the tools in MATLAB. The first was linspace. A second is discretize. A=[0.1, 0.21, 0.346, 0.59, 0.744, 1]; ...

Compare and modify random vector with evenly spaced vector

Again, learn to use the tools in MATLAB. The first was linspace. A second is discretize. A=[0.1, 0.21, 0.346, 0.59, 0.744, 1]; ...

20 Tage ago | 2

| accepted

Answered

re-looping after terminating

Trivial. Put the code INSIDE function. LEARN TO USE FUNCTIONS!!!!!! LEARN TO USE FUNCTIONS! LEARN TO USE FUNCTIONS! There, I sa...

re-looping after terminating

Trivial. Put the code INSIDE function. LEARN TO USE FUNCTIONS!!!!!! LEARN TO USE FUNCTIONS! LEARN TO USE FUNCTIONS! There, I sa...

21 Tage ago | 0

Answered

Solve not finding trivial zero

As always, you absolutely need to tell what release you are using, because this works with no problem. Done using R2019a: syms ...

Solve not finding trivial zero

As always, you absolutely need to tell what release you are using, because this works with no problem. Done using R2019a: syms ...

23 Tage ago | 0

| accepted

Answered

Matrix subtraction within Matlab

whos Name Size Bytes Class Attributes E 2x1 16 double ...

Matrix subtraction within Matlab

whos Name Size Bytes Class Attributes E 2x1 16 double ...

23 Tage ago | 3

Answered

Curve fitting WITHOUT toolbox and removing outliers from data.

There is no standard method. Why not? because outliers are different things from what you have normally, and vary for each probl...

Curve fitting WITHOUT toolbox and removing outliers from data.

There is no standard method. Why not? because outliers are different things from what you have normally, and vary for each probl...

24 Tage ago | 0

Answered

natural cubic spline interpolation

Learn to use the debugger. This is a basic problem. You know what line the problem is on, but even if you did not, then you coul...

natural cubic spline interpolation

Learn to use the debugger. This is a basic problem. You know what line the problem is on, but even if you did not, then you coul...

27 Tage ago | 0

Answered

Finding intersection using Newtons method

Firt, why are you writing rootfinding code, when tools like fzero exist? Don't write poorly written code when well written code ...

Finding intersection using Newtons method

Firt, why are you writing rootfinding code, when tools like fzero exist? Don't write poorly written code when well written code ...

27 Tage ago | 0

Answered

Is there any way to use intervals(Intlab) instead of real numbers when optimizing in Matlab?

The simple answer is, you probably can't. Think about how an optimization might work, Newton's method, for example. Given a st...

Is there any way to use intervals(Intlab) instead of real numbers when optimizing in Matlab?

The simple answer is, you probably can't. Think about how an optimization might work, Newton's method, for example. Given a st...

28 Tage ago | 0

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Answered

Why doesn't my fit converge?

Assuming you have some good reason to want to do this (something I seriously doubt is a good reason)... Why is it not convergin...

Why doesn't my fit converge?

Assuming you have some good reason to want to do this (something I seriously doubt is a good reason)... Why is it not convergin...

29 Tage ago | 0

| accepted

Answered

Assume and find different possible unknown variables of inequalities , Need help please

First, you cannot write a pair of inequalities that way in MATLAB. It works as a conventional form, because people know what you...

Assume and find different possible unknown variables of inequalities , Need help please

First, you cannot write a pair of inequalities that way in MATLAB. It works as a conventional form, because people know what you...

29 Tage ago | 0

Answered

How to solve this system of ODEs

You have ONE equation, not a system of ODEs. (a * dy/dt) + (b * y) = (c * dx/dt) + (d * x) But suppose you knew the true so...

How to solve this system of ODEs

You have ONE equation, not a system of ODEs. (a * dy/dt) + (b * y) = (c * dx/dt) + (d * x) But suppose you knew the true so...

30 Tage ago | 1

| accepted

Answered

isprime function seems to have poor performance

First, using isprime to test for primality of a Mersenne number is a bad idea. The Lucas-Lehmer test, is as I recall, much more ...

isprime function seems to have poor performance

First, using isprime to test for primality of a Mersenne number is a bad idea. The Lucas-Lehmer test, is as I recall, much more ...

etwa ein Monat ago | 1

| accepted

Answered

How can I solve a complicated symbolic integral

Your need is not relevant. Mathematics is not something that just works because you want it to. (Unless you have a magic wand, a...

How can I solve a complicated symbolic integral

Your need is not relevant. Mathematics is not something that just works because you want it to. (Unless you have a magic wand, a...

etwa ein Monat ago | 1

Answered

MATLAB for invoice comparisons

Of course it can. It would require learning MATLAB. It would require a clear understanding of what you are comparing, and what ...

MATLAB for invoice comparisons

Of course it can. It would require learning MATLAB. It would require a clear understanding of what you are comparing, and what ...

etwa ein Monat ago | 0

Answered

Integers can only be combined with integers of the same class, or scalar doubles.

READ THE ERROR MESSAGE! R = uint8(1:5); >> R./double(R) Error using ./ Integers can only be combined with integers of the ...

Integers can only be combined with integers of the same class, or scalar doubles.

READ THE ERROR MESSAGE! R = uint8(1:5); >> R./double(R) Error using ./ Integers can only be combined with integers of the ...

etwa ein Monat ago | 0

Answered

How to change non zero value into 0?

You want to reset the last 10 non-zeros to zero, in each column. So, let me build an example matrix. A = rand(20,5) > 0.25 A =...

How to change non zero value into 0?

You want to reset the last 10 non-zeros to zero, in each column. So, let me build an example matrix. A = rand(20,5) > 0.25 A =...

etwa ein Monat ago | 3

Answered

How to generate matrices that satisfies constraints on sum of row elements and sum of column elements?

You have 9 unknowns, with 6 linear equality constraints. The unknowns are bounded between 0 and 100. You don't say an upper boun...

How to generate matrices that satisfies constraints on sum of row elements and sum of column elements?

You have 9 unknowns, with 6 linear equality constraints. The unknowns are bounded between 0 and 100. You don't say an upper boun...

etwa ein Monat ago | 1

Answered

Matrix Equality Check Failed Using == and isequal

NEVER test for exact equality of floating point matrices. It won't happen, at least not unless you are very, very lucky. a_inv ...

Matrix Equality Check Failed Using == and isequal

NEVER test for exact equality of floating point matrices. It won't happen, at least not unless you are very, very lucky. a_inv ...

etwa ein Monat ago | 0

| accepted

Answered

randperm non uniformly distributed

Sigh. This is NOT a question of non-uniformity. Just a question of not understanding how to recognize non-uniformity, and partia...

randperm non uniformly distributed

Sigh. This is NOT a question of non-uniformity. Just a question of not understanding how to recognize non-uniformity, and partia...

etwa ein Monat ago | 1

| accepted

Answered

How to plot below multivalued function

But it is not a function, in some standard mathematical sense of the word. https://en.wikipedia.org/wiki/Function_(mathematics)...

How to plot below multivalued function

But it is not a function, in some standard mathematical sense of the word. https://en.wikipedia.org/wiki/Function_(mathematics)...

etwa ein Monat ago | 0

Answered

How to do discontinuous piecewise linear model fitting?

SLM is not designed to solve the discontinuous linear case, nor would I ever decide to modify the code to allow that. (Sorry, bu...

How to do discontinuous piecewise linear model fitting?

SLM is not designed to solve the discontinuous linear case, nor would I ever decide to modify the code to allow that. (Sorry, bu...

etwa ein Monat ago | 1

| accepted