1.108 total contributions since 2017

Knowledge means knowing where it is written...

Interested in:

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Answered

How to use VPA (variable precision arithmetic) in calculating HH band via dwt on an image?

You can not do this. dwt2 accepts only double as input and outputs double. vpa works on symbolic variables and returns a symboli...

How to use VPA (variable precision arithmetic) in calculating HH band via dwt on an image?

You can not do this. dwt2 accepts only double as input and outputs double. vpa works on symbolic variables and returns a symboli...

etwa 7 Stunden ago | 0

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Answered

String to Categorical array

x = [zeros(1,120), ones(1,240)]; res = categorical(x, [0, 1], {'Z', 'O'});

String to Categorical array

x = [zeros(1,120), ones(1,240)]; res = categorical(x, [0, 1], {'Z', 'O'});

etwa 8 Stunden ago | 0

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Answered

Reducing 2nd order ODE into coupled ODE. Solve using Euler Method and graph.

tspan = [0 5]; % time span to integrate y0 = [3 0]; % initial conditions %Start of Euler Method syms y(t) E = diff(y,2) + ...

Reducing 2nd order ODE into coupled ODE. Solve using Euler Method and graph.

tspan = [0 5]; % time span to integrate y0 = [3 0]; % initial conditions %Start of Euler Method syms y(t) E = diff(y,2) + ...

etwa 8 Stunden ago | 0

Answered

How to convert cell array to double?

c = {[1 2],[2 3]} s = cell2mat(c) s = unique(s)

How to convert cell array to double?

c = {[1 2],[2 3]} s = cell2mat(c) s = unique(s)

etwa 8 Stunden ago | 0

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Answered

hi,i am getting error as not enough input arguments,while i run the below code....?? please let me know that?(the error is in second line of code)

Works fine for me, if called with *_2_* input arguments: res = trio(3,4) function x=trio(m,n) x=rand([3*m n]); ...

hi,i am getting error as not enough input arguments,while i run the below code....?? please let me know that?(the error is in second line of code)

Works fine for me, if called with *_2_* input arguments: res = trio(3,4) function x=trio(m,n) x=rand([3*m n]); ...

etwa 19 Stunden ago | 0

Answered

How to solve coupled (differential) equations of motion using matlab?

Whta is the problem? There is an analytical solution (here assumed that vx0 and vz0 are equal to 1): syms w b g m x(t) y(t) z(t...

How to solve coupled (differential) equations of motion using matlab?

Whta is the problem? There is an analytical solution (here assumed that vx0 and vz0 are equal to 1): syms w b g m x(t) y(t) z(t...

ein Tag ago | 0

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Answered

Undefined operator '/' for input arguments of type 'function_handle'

b=400; %mm d=500; %mm Asv = [3000 5000 3000 5000]; %mm^2 fckv = [30 30 90 90]; %Mpa num_fckv = numel(fckv); fsolve_opt...

Undefined operator '/' for input arguments of type 'function_handle'

b=400; %mm d=500; %mm Asv = [3000 5000 3000 5000]; %mm^2 fckv = [30 30 90 90]; %Mpa num_fckv = numel(fckv); fsolve_opt...

ein Tag ago | 0

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Answered

Can't plot function

x = linspace(0,10); y = sqrt(1+x.^2)./sqrt(x.^4-x.^2+1); plot(x,y)

Can't plot function

x = linspace(0,10); y = sqrt(1+x.^2)./sqrt(x.^4-x.^2+1); plot(x,y)

2 Tage ago | 1

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Answered

Fit Powerlaw to Data

https://de.mathworks.com/help/curvefit/custom-nonlinear-models.html

Fit Powerlaw to Data

https://de.mathworks.com/help/curvefit/custom-nonlinear-models.html

3 Tage ago | 0

Answered

Numerical Solution for a System of Three ODEs with Different Constant for Each Time Element

Use interp1 for this. Here is an example: https://de.mathworks.com/matlabcentral/answers/487412-using-ode45-to-solve-differenti...

Numerical Solution for a System of Three ODEs with Different Constant for Each Time Element

Use interp1 for this. Here is an example: https://de.mathworks.com/matlabcentral/answers/487412-using-ode45-to-solve-differenti...

4 Tage ago | 0

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Answered

Text file manipulation, find specific lines, find there a string and replace the specific line with new content

There is a bunch of possibilities to manipulate strings: https://de.mathworks.com/help/matlab/ref/extractafter.html https://de...

Text file manipulation, find specific lines, find there a string and replace the specific line with new content

There is a bunch of possibilities to manipulate strings: https://de.mathworks.com/help/matlab/ref/extractafter.html https://de...

4 Tage ago | 0

Answered

Fitting an equation to a Sine Function with NonLinearModel.fit

"...I already tried using the "cftool" function in matlab but it did not have the equation I need...." Did you notice that yo...

Fitting an equation to a Sine Function with NonLinearModel.fit

"...I already tried using the "cftool" function in matlab but it did not have the equation I need...." Did you notice that yo...

4 Tage ago | 0

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Answered

How to replace last 3 digits in a floating point number by another 3 digits

format long x = -3.141592653589793; a = 287; x_new = sprintf('%.15f',x); x_new(end-2:end) = (sprintf('%d',a)); x_new = st...

How to replace last 3 digits in a floating point number by another 3 digits

format long x = -3.141592653589793; a = 287; x_new = sprintf('%.15f',x); x_new(end-2:end) = (sprintf('%d',a)); x_new = st...

4 Tage ago | 0

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Answered

I am trying to use ODE45, but I keep getting an error with myfcn saying I don't have enough inputs?

There are at least 4 problems in your code: 1. Split your main code and your ode function: tspan = [0 10]; f0 = [0 0]; ...

I am trying to use ODE45, but I keep getting an error with myfcn saying I don't have enough inputs?

There are at least 4 problems in your code: 1. Split your main code and your ode function: tspan = [0 10]; f0 = [0 0]; ...

4 Tage ago | 1

Answered

Having trouble with ODE45 and a System of Ordinary Differential Equations

For every equation you have to input an initial condition. You have 8 but only give 2 initial conditions to ode45. Also your ...

Having trouble with ODE45 and a System of Ordinary Differential Equations

For every equation you have to input an initial condition. You have 8 but only give 2 initial conditions to ode45. Also your ...

5 Tage ago | 0

Answered

Is there a function to turn ?x2 matrix of coordinates of vertices of a polygon into a ?x4 matrix of coordinates of line segments of that polygon?

Yes, circshift will do the job: A = [2, 4; 5, 6; 6, 6; 8,5] B = [2, 4, 5, 6; 5, 6, 6, 6; 6, 6, 8, 5; 8, 5, 2, 4] % The sol...

Is there a function to turn ?x2 matrix of coordinates of vertices of a polygon into a ?x4 matrix of coordinates of line segments of that polygon?

Yes, circshift will do the job: A = [2, 4; 5, 6; 6, 6; 8,5] B = [2, 4, 5, 6; 5, 6, 6, 6; 6, 6, 8, 5; 8, 5, 2, 4] % The sol...

5 Tage ago | 0

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Answered

could anyone help me to display the values in the matrix which are greater than the average value for the following code

B, C and D are not needed, if you use the inbuilt function mean: A=[3.3734 5.1245 4.3729 2.8406 6.5283 4.8144 ...

could anyone help me to display the values in the matrix which are greater than the average value for the following code

B, C and D are not needed, if you use the inbuilt function mean: A=[3.3734 5.1245 4.3729 2.8406 6.5283 4.8144 ...

5 Tage ago | 0

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Answered

How can calcuate the lines of code efficiently?

Yes, you can if you avoid using a loop and vectorize your code - see here: tic %%%code nx=512; ny=nx; dx=1; dy=dx; format...

How can calcuate the lines of code efficiently?

Yes, you can if you avoid using a loop and vectorize your code - see here: tic %%%code nx=512; ny=nx; dx=1; dy=dx; format...

5 Tage ago | 1

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Answered

how can i differentiate a constant in simulink?

You already have done everything exactly correct - Simulink also did what is correct. What is the derivative of y(t)=3 with resp...

how can i differentiate a constant in simulink?

You already have done everything exactly correct - Simulink also did what is correct. What is the derivative of y(t)=3 with resp...

5 Tage ago | 0

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Answered

Eigenvalues and Eigenvectors of Symbolic Matrix

syms E t H = [E -t -t -t -t 0 0 0 0;-t E 0 0 0 -t -t 0 0;-t 0 E 0 0 0 0 -t -t;... -t 0 0 E 0 -t 0 -t 0; -t 0 0 0 E 0 -t 0...

Eigenvalues and Eigenvectors of Symbolic Matrix

syms E t H = [E -t -t -t -t 0 0 0 0;-t E 0 0 0 -t -t 0 0;-t 0 E 0 0 0 0 -t -t;... -t 0 0 E 0 -t 0 -t 0; -t 0 0 0 E 0 -t 0...

5 Tage ago | 0

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Answered

what is wrong with my script

clear all for loop_index = 1:2 x = input('Input number to convert'); units = input('Input the units to convert from','s...

what is wrong with my script

clear all for loop_index = 1:2 x = input('Input number to convert'); units = input('Input the units to convert from','s...

5 Tage ago | 1

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Answered

Any trick to name a variable with decimal number?

No, it is simply not allowed in Matlab. No way, no trick: https://de.mathworks.com/help/matlab/matlab_prog/variable-names.html#...

Any trick to name a variable with decimal number?

No, it is simply not allowed in Matlab. No way, no trick: https://de.mathworks.com/help/matlab/matlab_prog/variable-names.html#...

6 Tage ago | 0

Answered

PULL OUT A SPECIFIC WORD FROM A LONG STRING

You might want to start reading here: https://de.mathworks.com/help/matlab/matlab_prog/searching-and-replacing.html

PULL OUT A SPECIFIC WORD FROM A LONG STRING

You might want to start reading here: https://de.mathworks.com/help/matlab/matlab_prog/searching-and-replacing.html

6 Tage ago | 1

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Answered

How do I create a for loop to extract data from table?

No loop is needed: A = unstack(ReactionTime,'RESPONSE_TIME_ehmi','videostring') since you have invalid names for you video fil...

How do I create a for loop to extract data from table?

No loop is needed: A = unstack(ReactionTime,'RESPONSE_TIME_ehmi','videostring') since you have invalid names for you video fil...

6 Tage ago | 0

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Answered

complement of an image

I = fliplr(imread('cameraman.tif')); I1 = triu((I),1); I2 = tril(imcomplement(I)); I_res = fliplr(I1+I2); imshow(I_res) B...

complement of an image

I = fliplr(imread('cameraman.tif')); I1 = triu((I),1); I2 = tril(imcomplement(I)); I_res = fliplr(I1+I2); imshow(I_res) B...

6 Tage ago | 1

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Answered

Trapz gives "Second and third argument must either be variables or a variable and a nonnegative integer specifying the number of differentiations."

syms x f_scalar = @(x) 5*x^2+3*x-4; g_scalar = @(x) -4*x^2+6*x+5; f = @(vec) arrayfun(f_scalar,vec); g = @(vec) arrayfun(g_sca...

Trapz gives "Second and third argument must either be variables or a variable and a nonnegative integer specifying the number of differentiations."

syms x f_scalar = @(x) 5*x^2+3*x-4; g_scalar = @(x) -4*x^2+6*x+5; f = @(vec) arrayfun(f_scalar,vec); g = @(vec) arrayfun(g_sca...

6 Tage ago | 0

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Answered

Problem with input of ode113

I_1= pi^2; I_2= -2*pi^2; params.tau= 10; g= 0; V_1= -65; V_2= -65; state= [V_1;V_2]; I= [I_1;I_2]; options = odeset('ab...

Problem with input of ode113

I_1= pi^2; I_2= -2*pi^2; params.tau= 10; g= 0; V_1= -65; V_2= -65; state= [V_1;V_2]; I= [I_1;I_2]; options = odeset('ab...

7 Tage ago | 0

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Answered

How to define discrete variables in GA (genetic algorithm)

https://de.mathworks.com/matlabcentral/answers/401059-setup-discrete-values-for-decision-variables-in-optimization-problems

How to define discrete variables in GA (genetic algorithm)

https://de.mathworks.com/matlabcentral/answers/401059-setup-discrete-values-for-decision-variables-in-optimization-problems

7 Tage ago | 0

Answered

Surrogate search with integer parameters

|*intcon*| was introduced to surrogateopt in R2019b. <https://de.mathworks.com/help/gads/release-notes.html>

Surrogate search with integer parameters

|*intcon*| was introduced to surrogateopt in R2019b. <https://de.mathworks.com/help/gads/release-notes.html>

7 Tage ago | 0

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Answered

Accessing value in a cell

Edited because of the comments: a = {'1,65,4,5'} b = str2num(a{:}) b(2)

Accessing value in a cell

Edited because of the comments: a = {'1,65,4,5'} b = str2num(a{:}) b(2)

8 Tage ago | 1

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