44.641 total contributions since 2011

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Answered

How do I get a symbolic differentiation of cfit/sfit functions?

When sf is the fit object, f = subs(str2sym(formula(sf)),coeffnames(sf),num2cell(coeffvalues(sf).')); vars = sym(indepnames(sf...

How do I get a symbolic differentiation of cfit/sfit functions?

When sf is the fit object, f = subs(str2sym(formula(sf)),coeffnames(sf),num2cell(coeffvalues(sf).')); vars = sym(indepnames(sf...

alrededor de 2 horas ago | 0

Answered

Error - Index in position 1 is invalid. Array indices must be positive integers or logical values.

for i = 1:10; The first time through the loop, i will be assigned the value 1 Y=abs(atan((A(i-1,2)-A(i,2)/2000))); The fi...

Error - Index in position 1 is invalid. Array indices must be positive integers or logical values.

for i = 1:10; The first time through the loop, i will be assigned the value 1 Y=abs(atan((A(i-1,2)-A(i,2)/2000))); The fi...

alrededor de 6 horas ago | 0

Answered

why values of multiwavlet transform have larger values of input?

The simplest wavelet predicts +1 for the first half and -1 for the second half. Suppose you had an input that was [64 64 64 64]...

why values of multiwavlet transform have larger values of input?

The simplest wavelet predicts +1 for the first half and -1 for the second half. Suppose you had an input that was [64 64 64 64]...

alrededor de 6 horas ago | 0

Answered

i want to find the solution to an equation containing bessel function x*besselj(1,x)-C*besselj(0,x). I am using newton raphson method but I am getting NaN as the root.

x(1) is 0. besselj(1,0) is 0 and Bi*0 is 0. besslj(0,0) is 1, but you multiply that by x(1) which is 0. So your denominator of y...

i want to find the solution to an equation containing bessel function x*besselj(1,x)-C*besselj(0,x). I am using newton raphson method but I am getting NaN as the root.

x(1) is 0. besselj(1,0) is 0 and Bi*0 is 0. besslj(0,0) is 1, but you multiply that by x(1) which is 0. So your denominator of y...

alrededor de 7 horas ago | 0

Answered

How to write this loop?

%% readDataFromFile and WriteDataToFile are given functions %% stress.out is a file containing a matrix of 195 elements fu...

How to write this loop?

%% readDataFromFile and WriteDataToFile are given functions %% stress.out is a file containing a matrix of 195 elements fu...

alrededor de 7 horas ago | 0

Answered

direct convert to float64 from the data of output of fread

swapbytes(typecast(uint8(data),'double'))

direct convert to float64 from the data of output of fread

swapbytes(typecast(uint8(data),'double'))

alrededor de 8 horas ago | 0

| accepted

Answered

extract the words from audio file

part1=p1(1:floor(q*1.5),:); part2=p1(ceil(1.5*q):floor(q*2.5), :); part3=p1(ceil(2.5*q):floor(q*3),end, :);

extract the words from audio file

part1=p1(1:floor(q*1.5),:); part2=p1(ceil(1.5*q):floor(q*2.5), :); part3=p1(ceil(2.5*q):floor(q*3),end, :);

alrededor de 9 horas ago | 0

Answered

Find the solution to the differential equation

N(t) = 1.5x^2 -2x +3 That equation does not reflect your original question dy/dx = 1.5x^2 -2x +3 . The difference is in the var...

Find the solution to the differential equation

N(t) = 1.5x^2 -2x +3 That equation does not reflect your original question dy/dx = 1.5x^2 -2x +3 . The difference is in the var...

alrededor de 9 horas ago | 0

| accepted

Answered

How to add different size arrays to existing graph

fig = openfig('SolarIrradiance.fig'); existing_line = findobj(fig, 'type', 'line'); ax = ancestor(existing_line, 'axes'); lam...

How to add different size arrays to existing graph

fig = openfig('SolarIrradiance.fig'); existing_line = findobj(fig, 'type', 'line'); ax = ancestor(existing_line, 'axes'); lam...

alrededor de 10 horas ago | 0

Answered

Using Accumarray with @maxk instead of @max?

accumarray(a(:,1), max(b,c), [], @(v) mean(maxk(v,3)), 0, true) %final parameter is sparse flag

Using Accumarray with @maxk instead of @max?

accumarray(a(:,1), max(b,c), [], @(v) mean(maxk(v,3)), 0, true) %final parameter is sparse flag

alrededor de 10 horas ago | 0

Answered

How to read information from a .txt file and convert it into a matrix

S = fileread('frotatego'); info_struct = regexp(S, '^(?<name>.*?)\s+(?<val1>\d+\.\d\d)\s+(?<val2>\d+\.\d\d)\s*$', 'names', 'dot...

How to read information from a .txt file and convert it into a matrix

S = fileread('frotatego'); info_struct = regexp(S, '^(?<name>.*?)\s+(?<val1>\d+\.\d\d)\s+(?<val2>\d+\.\d\d)\s*$', 'names', 'dot...

alrededor de 10 horas ago | 0

Answered

How to let a numerical field to be assigned preferrentially by user input?

Just always fetch the current version of the field; if the user hasn't modified the values since the last time then they will be...

How to let a numerical field to be assigned preferrentially by user input?

Just always fetch the current version of the field; if the user hasn't modified the values since the last time then they will be...

alrededor de 11 horas ago | 0

Answered

Finding the distance between a large group of points from a plane

https://www.mathworks.com/help/stats/knnsearch.html knnsearch() between the wall points and the cloud points. This does not co...

Finding the distance between a large group of points from a plane

https://www.mathworks.com/help/stats/knnsearch.html knnsearch() between the wall points and the cloud points. This does not co...

alrededor de 11 horas ago | 0

Answered

Chaotic bit stream cipher

Logicists maps can be used for this purposes, as they only need to know the current state. "cat map" on the other hand requires...

Chaotic bit stream cipher

Logicists maps can be used for this purposes, as they only need to know the current state. "cat map" on the other hand requires...

alrededor de 11 horas ago | 0

Answered

Which interpolation method is best?

Use https://www.mathworks.com/help/matlab/ref/fillmissing.html#bva1z1c-method fillmissing() -- it supports all of the methods yo...

Which interpolation method is best?

Use https://www.mathworks.com/help/matlab/ref/fillmissing.html#bva1z1c-method fillmissing() -- it supports all of the methods yo...

alrededor de 12 horas ago | 0

Answered

How to read and process a text file?

S = fileread('sample.txt'); S = regexprep(S, {'^\$.*?\n', '\r'}, {'', ''}, 'lineanchors'); all_ids = string(regexp(S, '^\S*', ...

How to read and process a text file?

S = fileread('sample.txt'); S = regexprep(S, {'^\$.*?\n', '\r'}, {'', ''}, 'lineanchors'); all_ids = string(regexp(S, '^\S*', ...

alrededor de 12 horas ago | 0

Answered

Every time during the starting of MATLAB these two warnings pop up?

https://www.mathworks.com/matlabcentral/answers/472134-gtk-message-10-32-31-466-failed-to-load-module-canberra-gtk-module

Every time during the starting of MATLAB these two warnings pop up?

https://www.mathworks.com/matlabcentral/answers/472134-gtk-message-10-32-31-466-failed-to-load-module-canberra-gtk-module

alrededor de 24 horas ago | 0

Answered

jetson function package not found

https://www.mathworks.com/help/supportpkg/nvidia/ref/jetson.jetson.html GPU Coder Support For Nvidia GPU is the required supp...

jetson function package not found

https://www.mathworks.com/help/supportpkg/nvidia/ref/jetson.jetson.html GPU Coder Support For Nvidia GPU is the required supp...

alrededor de 24 horas ago | 0

Answered

Multiple print outside of loop

Your c is a vector because of the rand(100, 1) None of the code is expecting a vector for c. Note that if you are trying t...

Multiple print outside of loop

Your c is a vector because of the rand(100, 1) None of the code is expecting a vector for c. Note that if you are trying t...

1 día ago | 0

| accepted

Answered

my code doesnt show a graph even if i use the plot command

sinoaz=-23.45*(pi/180)*cos(((2*pi)/365)*(10+n)); Should use n_days instead of n A=asind(sinAz); Should be A(...

my code doesnt show a graph even if i use the plot command

sinoaz=-23.45*(pi/180)*cos(((2*pi)/365)*(10+n)); Should use n_days instead of n A=asind(sinAz); Should be A(...

1 día ago | 0

Answered

Image Write in Excel

https://answers.microsoft.com/en-us/msoffice/forum/all/what-is-the-maximum-number-of-columns-in-a/5a053135-4865-e011-8dfc-68b599...

Image Write in Excel

https://answers.microsoft.com/en-us/msoffice/forum/all/what-is-the-maximum-number-of-columns-in-a/5a053135-4865-e011-8dfc-68b599...

1 día ago | 0

Answered

coswm should have a 1x365 dimension, but its dimension is 1x1, what am i doing wrong?

The / operator is Matrix Right Divide, which is least squares fitting effectively. If you did not intend to do fitting at that p...

coswm should have a 1x365 dimension, but its dimension is 1x1, what am i doing wrong?

The / operator is Matrix Right Divide, which is least squares fitting effectively. If you did not intend to do fitting at that p...

1 día ago | 0

| accepted

Answered

How can I know if my laptop is plugged into AC power via Matlab?

<https://stackoverflow.com/questions/21249419/how-do-i-programatically-detect-if-my-laptop-is-plugged-in-or-not-osx> You can ...

How can I know if my laptop is plugged into AC power via Matlab?

<https://stackoverflow.com/questions/21249419/how-do-i-programatically-detect-if-my-laptop-is-plugged-in-or-not-osx> You can ...

1 día ago | 0

Answered

I have MatlabR2019b and I am trying to do a simple plot. I am not able to plot anything unless I use scatter(x,y) or area(x,y). How could I get plot(x,y) to work? I am using a Mac.

You need to rename plot.m in the untitled folder directory as it is overriding the Mathworks plot call

I have MatlabR2019b and I am trying to do a simple plot. I am not able to plot anything unless I use scatter(x,y) or area(x,y). How could I get plot(x,y) to work? I am using a Mac.

You need to rename plot.m in the untitled folder directory as it is overriding the Mathworks plot call

2 días ago | 1

| accepted

Answered

Error Message Using ODE45

The part starting from [t,y] = ode45(@vdp1,[0 20],[2; 0]); plot(t,y(:,1),'-o',t,y(:,2),'-o') Should be in a differen...

Error Message Using ODE45

The part starting from [t,y] = ode45(@vdp1,[0 20],[2; 0]); plot(t,y(:,1),'-o',t,y(:,2),'-o') Should be in a differen...

2 días ago | 0

Answered

fsolve to solve 5th order polynomial

You have an equation of the form A=B. Subtract B from both sides giving an equation of the form (A) - (B) = 0. Now you can fsolv...

fsolve to solve 5th order polynomial

You have an equation of the form A=B. Subtract B from both sides giving an equation of the form (A) - (B) = 0. Now you can fsolv...

2 días ago | 1

Answered

How to convert a grey-scale image into a reverse binary image

Rbin = YourImage <= 42;

How to convert a grey-scale image into a reverse binary image

Rbin = YourImage <= 42;

3 días ago | 0

| accepted

Answered

Using timer, How can I cleanly exit a function execution, when the timer fires in MATLAB?

There are only four ways in MATLAB to force a function to stop executing without its cooperation: quit MATLAB force an out-of-...

Using timer, How can I cleanly exit a function execution, when the timer fires in MATLAB?

There are only four ways in MATLAB to force a function to stop executing without its cooperation: quit MATLAB force an out-of-...

3 días ago | 0

Answered

Getting a empty sym 0x1 error when I run this code

[dP,dVg,dVf,dTf,dTg] = solve([eq1,eq2,eq3,eq4,eq5],[dP,dVg,dVf,dTf,dTg])

Getting a empty sym 0x1 error when I run this code

[dP,dVg,dVf,dTf,dTg] = solve([eq1,eq2,eq3,eq4,eq5],[dP,dVg,dVf,dTf,dTg])

3 días ago | 0

Answered

Treating input arguments (not paying attention to order of number)

Use name/value pairs, unless there is something inside of the structs that identifies which kind of object it is for, or some ot...

Treating input arguments (not paying attention to order of number)

Use name/value pairs, unless there is something inside of the structs that identifies which kind of object it is for, or some ot...

3 días ago | 0

| accepted