Answered

fsolve cant find a solution for some points

It is actually pretty simple to solve this. Remember that fsolve uses a basic algorithm. Start the problem out in the wrong plac...

fsolve cant find a solution for some points

It is actually pretty simple to solve this. Remember that fsolve uses a basic algorithm. Start the problem out in the wrong plac...

7 hours ago | 2

Answered

lower and upper index in sorted vector

Please don't post pictures of numbers. That makes it more difficult to help you, to answer your question. Why would you make it ...

lower and upper index in sorted vector

Please don't post pictures of numbers. That makes it more difficult to help you, to answer your question. Why would you make it ...

22 hours ago | 0

| accepted

Answered

When does randomness enter a shuffled "deck" of coin tosses.

I put together this simple script. In it you will find perhaps the most efficient scheme for a riffle shuffle that I know of, si...

When does randomness enter a shuffled "deck" of coin tosses.

I put together this simple script. In it you will find perhaps the most efficient scheme for a riffle shuffle that I know of, si...

1 day ago | 0

| accepted

Answered

command window does not recognize the functions in editor

I think you need to learn about the MATLAB search path. While the editor can save a file anywhere you tell it to, when executin...

command window does not recognize the functions in editor

I think you need to learn about the MATLAB search path. While the editor can save a file anywhere you tell it to, when executin...

2 days ago | 0

| accepted

Answered

Binary Quadratic Programming Relaxation

While you could just use a tool like quadprog with continuous varibles in the interval [0,1], then round the result at the end, ...

Binary Quadratic Programming Relaxation

While you could just use a tool like quadprog with continuous varibles in the interval [0,1], then round the result at the end, ...

2 days ago | 0

Answered

Tools used for Sparse Matrix Efficiency

Whoever gave you that advice, about never building a sparse matrix one element at a time must have been very knowledgable, as it...

Tools used for Sparse Matrix Efficiency

Whoever gave you that advice, about never building a sparse matrix one element at a time must have been very knowledgable, as it...

2 days ago | 1

Answered

Fibonacci even numbers. Code doesn't work for large numbers

Why are you surprised? log2(fibonacci(100)) ans = 68.263 You cannot represent an integer exactly in double precision ...

Fibonacci even numbers. Code doesn't work for large numbers

Why are you surprised? log2(fibonacci(100)) ans = 68.263 You cannot represent an integer exactly in double precision ...

3 days ago | 3

| accepted

Answered

Block Tri-diagonal Matrix

It may be your lucky day. Just download my blktridiag code from the file exchange. https://www.mathworks.com/matlabcentral/file...

Block Tri-diagonal Matrix

It may be your lucky day. Just download my blktridiag code from the file exchange. https://www.mathworks.com/matlabcentral/file...

3 days ago | 0

| accepted

Answered

i=1, 2, 3,,, However, when (a-i)> 0 is calculated.

Or, with no loop at all, and no test required. Just i = 1:a-1; station(i+2) = (4-(4-i))*N; This will define the entire vector...

i=1, 2, 3,,, However, when (a-i)> 0 is calculated.

Or, with no loop at all, and no test required. Just i = 1:a-1; station(i+2) = (4-(4-i))*N; This will define the entire vector...

3 days ago | 0

Answered

How to measure the correct circularity??

It would not be unusual for that measure to exceeds 1. For example, given a circle, we would have a perimeter of 2*pi*r. So perm...

How to measure the correct circularity??

It would not be unusual for that measure to exceeds 1. For example, given a circle, we would have a perimeter of 2*pi*r. So perm...

3 days ago | 0

Answered

Fitting an exponential using nlinfit

Most of the code you posted is meaningless, since you save only the variables whos Name Size Bytes ...

Fitting an exponential using nlinfit

Most of the code you posted is meaningless, since you save only the variables whos Name Size Bytes ...

4 days ago | 0

Answered

random integer condition selection

You want to generate a random number of random numbers? With an additional constraint that all are greater than 0.5? This is far...

random integer condition selection

You want to generate a random number of random numbers? With an additional constraint that all are greater than 0.5? This is far...

4 days ago | 1

Answered

[Solved] Upsampling multidimensional array with interpn

That is NOT a 5 dimensional array. While you may THINK of it as a set of points that live in 5 dimensions, it is NOT a 5-d arra...

[Solved] Upsampling multidimensional array with interpn

That is NOT a 5 dimensional array. While you may THINK of it as a set of points that live in 5 dimensions, it is NOT a 5-d arra...

4 days ago | 0

| accepted

Answered

Plotting a function (Horner Schema)

While polynomic psychological analysis seems well beyond my talents, Horner's rule is pretty easy. :) And since you made a credi...

Plotting a function (Horner Schema)

While polynomic psychological analysis seems well beyond my talents, Horner's rule is pretty easy. :) And since you made a credi...

5 days ago | 1

| accepted

Answered

Matlab says the matrix is not symmetric

D = rand(100); D = (D + D.')/2; issymmetric(D) ans = logical 1

Matlab says the matrix is not symmetric

D = rand(100); D = (D + D.')/2; issymmetric(D) ans = logical 1

5 days ago | 1

| accepted

Answered

how can i create a circle with a face color changing radially

[x,y] = meshgrid(linspace(-3,3)); z = exp(-x.^2 - y.^2); H = pcolor(z); H.LineStyle = 'none'; colormap(jet) axis equal ...

how can i create a circle with a face color changing radially

[x,y] = meshgrid(linspace(-3,3)); z = exp(-x.^2 - y.^2); H = pcolor(z); H.LineStyle = 'none'; colormap(jet) axis equal ...

5 days ago | 0

| accepted

Answered

Fit a curve on scatter data (main behaviuor)

You "want" the green line. I want the Buffalo Bills to win the Super bowl. Probably not gonna happen in either case. ;-) You wa...

Fit a curve on scatter data (main behaviuor)

You "want" the green line. I want the Buffalo Bills to win the Super bowl. Probably not gonna happen in either case. ;-) You wa...

5 days ago | 0

Answered

How can I understand why certain sets of random variates lead to the warning message "Unable to meet integration tolerances without reducing the step size below the smallest value allowed (1.136868e-13) at time t=51"?

Nobody yet wants to explain it? The standard reason for this error is because you are creating a problem that is too stiff for ...

How can I understand why certain sets of random variates lead to the warning message "Unable to meet integration tolerances without reducing the step size below the smallest value allowed (1.136868e-13) at time t=51"?

Nobody yet wants to explain it? The standard reason for this error is because you are creating a problem that is too stiff for ...

5 days ago | 3

| accepted

Answered

What am I getting wrong with trying to create a sphere mesh using a golden spiral?

So you are not looking for a mesh at all, just a uniform sampling? Simplest might be to use a random sampling, with a twist. Tha...

What am I getting wrong with trying to create a sphere mesh using a golden spiral?

So you are not looking for a mesh at all, just a uniform sampling? Simplest might be to use a random sampling, with a twist. Tha...

6 days ago | 0

| accepted

Answered

Why do I get a graph that is symmetrical based on x=-2 when I draw a graph of y1=4*log((x+2))?

It is not clear what you wanted to plot. However, I think you misunderstand. It is still possible to evaluate the log of a nega...

Why do I get a graph that is symmetrical based on x=-2 when I draw a graph of y1=4*log((x+2))?

It is not clear what you wanted to plot. However, I think you misunderstand. It is still possible to evaluate the log of a nega...

7 days ago | 0

Answered

Tabulated Gauss-Kronrod weights and abscissae

I might presume the mp indicates some variation of the multi-precision toolbox. An old free version has been on the File Exchang...

Tabulated Gauss-Kronrod weights and abscissae

I might presume the mp indicates some variation of the multi-precision toolbox. An old free version has been on the File Exchang...

7 days ago | 0

Answered

Solving symbolic trig equation

You can NEVER solve for those variables, at least as the equations are written. First of all, z never even appears. But since y...

Solving symbolic trig equation

You can NEVER solve for those variables, at least as the equations are written. First of all, z never even appears. But since y...

7 days ago | 1

| accepted

Answered

How to get the value of an extra variable with fsolve

The simple trick is to use the output arguments from a function. Change your function header to look like this: function [F,r...

How to get the value of an extra variable with fsolve

The simple trick is to use the output arguments from a function. Change your function header to look like this: function [F,r...

7 days ago | 0

| accepted

Answered

Find the intersection points between two data sets

Finding the intersection point is easy enough. [intx,inty] = intersections(data1(:,1),data1(:,2),data2(:,1),data2(:,2)) intx =...

Find the intersection points between two data sets

Finding the intersection point is easy enough. [intx,inty] = intersections(data1(:,1),data1(:,2),data2(:,1),data2(:,2)) intx =...

8 days ago | 1

| accepted

Answered

numerical solution of a system of ODE which is not in standard form

Your question seems to be one of solving a system of ODEs with a mass matrix. For example in the help for ODE45, we see this opt...

numerical solution of a system of ODE which is not in standard form

Your question seems to be one of solving a system of ODEs with a mass matrix. For example in the help for ODE45, we see this opt...

9 days ago | 1

Answered

calculate tension by raphson newton in matlab

You have indicated these coefficients, although I worry there may be issues, because of the use of lower versus upper case W, et...

calculate tension by raphson newton in matlab

You have indicated these coefficients, although I worry there may be issues, because of the use of lower versus upper case W, et...

9 days ago | 0

Answered

Interpolating n-dimensional functions

First, IF you have a complete gridded lattice, then you don't want to use griddatan. That is DEFINITELY a BAD idea. Why? Because...

Interpolating n-dimensional functions

First, IF you have a complete gridded lattice, then you don't want to use griddatan. That is DEFINITELY a BAD idea. Why? Because...

9 days ago | 1

| accepted

Answered

What am I missing here?

Thank you. That makes it much easier for someone to offer you help. Now I'll be willing to look at the problem you had. It loo...

What am I missing here?

Thank you. That makes it much easier for someone to offer you help. Now I'll be willing to look at the problem you had. It loo...

10 days ago | 1

Answered

How to extrapolate a contour plot?

Let me see. You have data in only 25% of the region of interest. Now you want to extrapolate that data into a region that compri...

How to extrapolate a contour plot?

Let me see. You have data in only 25% of the region of interest. Now you want to extrapolate that data into a region that compri...

11 days ago | 0

Answered

To solve non-linear equation by inversion notion

STOP. Is this nonlinear? Or is it linear? A*X = b is still LINEAR, even if the array is not square. Even in the linear case, t...

To solve non-linear equation by inversion notion

STOP. Is this nonlinear? Or is it linear? A*X = b is still LINEAR, even if the array is not square. Even in the linear case, t...

11 days ago | 0