Community Profile # Matthew Worker

Active since 2013

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hi I want to solve this problem using posted script.
Problem: Another formula for computing "pi" can be deduced from the identity pi/4 = 4arctan1/5— arctan1/239. Determine the numbe...

23 días ago | 1 answer | 0

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Question

I want find the reason for this error message.
I am having trouble finding the reason behind this error message. I chechked my function again and again. but do not know why it...

26 días ago | 1 answer | 0

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Question

how to draw a directional field for this equation?
I am trying to plot directional field for these differential eq.s a) y’= 0.1y-sin(y) b) y’ = y^2-3*y+1 c) y’ = -y(y-2)(y-4)/...

30 días ago | 1 answer | 0

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Question

How to write following equation with "dsolve" command?
I have written the code as below for the equation : on MATLAB command window, syms y(t); eqn = diff(y,t) == t^2/(1+y^2)...

alrededor de 1 mes ago | 2 answers | 0

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Question

How to write diff (exp(x.*log(x))) on MATLAB command window?
I am trying to compute the derivative using the command diff: syms x diff (exp(x.*log(x))) Error using sym/su...

alrededor de 1 mes ago | 0 answers | 0

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Question

High Resolution fft2 image
Hello All, Please help me on the following- I need to construct an Fourier Transormed image such an Fig.1, But so far I have go...

5 meses ago | 1 answer | 0

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Question

Power loss minimisation using fmincon
I need to minimise my power losses using fmincon with constraints. the Values that i am using are: Vm=230; Rmk=0.0246; Rkn=0.0...

6 meses ago | 3 answers | 1

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Question

Runge-Kutta 4th Order on a 2nd Order ODE
I am dealing with the following 2nd order ODE: With initial conditions of: , , . and should be 3.24 I have found the sys...

8 meses ago | 1 answer | 0

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Question

How can I create a 3D array?
for i=1:n-1 Image2 = uigetfile('*p*'); ImageArray2 =imread(Image2); MDArray = cat(3,ImageArray,[ImageArray2])...

9 meses ago | 1 answer | 0

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Question

Subtraction matrix for all values
column 1 - column 2; column 1 - column 3; column 1 - column 4...(rest of subtractions)..olumn 4 - column 4. How would I appr...

10 meses ago | 1 answer | 0

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Question

Not sure how to solve equations using newton-Raphson method
Can anyone help me solve these two equation using newton-raphson method 5/2*cos(x(1))+3*cos(x(1)+x(2))-5 5/2*sin(x(1))+3*sin(x...

10 meses ago | 1 answer | 0

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Question

Does anyone have any resources for modelling a distribution network and charging an electric vehicle from it
I want to do a project that solves an optimisation task for Electric Vechile charging from the Low-Voltage power network. Howeve...

12 meses ago | 1 answer | 0

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Question

Filenames in MATLAB - directory
Hello, So currently, what I'm doing it's prompting out window to select folder, I then was thinking of using a foor loop that ...

12 meses ago | 1 answer | 0

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Question

Hi guys, I wanted to get an idea on how I should approach a problem. Say for example I have a 100x48 matrix and I want to get ...

más de 1 año ago | 1 answer | 0

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Question

How to find settling time?
Hello I want to be able to find the time taken (number of frames) for each of the peaks to reach the new stabilising value in ...

más de 1 año ago | 1 answer | 0

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How to locate significant points in a graph?
Hi So I've plotted a graph of two variables from a 118000x2 matrix: Frames and Conductivity. I've attached a picture of the gra...

más de 1 año ago | 1 answer | 0

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Question

4d plotting with slices
Hello :) I have 4d data (x y z coordinates and and V). I am hoping to represent the data similar to the slice function approa...

casi 2 años ago | 1 answer | 0

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Question

Plot 4d data
hi :) how can one import an excel sheet with x, y, z and V columns as a 3d matrix? I am trying to plot the V values over a co or...

casi 2 años ago | 1 answer | 0

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Question

Trouble with MATLAB Triple Integral
I'm attempting to evaluate this integral (and equation) where 'a' and 'x' are just inputs, and x' is (x,y,z). also: x will hav...

alrededor de 2 años ago | 1 answer | 0

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Question

Beginner MATLAB question (I just started using matlab a week ago)

más de 2 años ago | 1 answer | 0

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Dummy Variable ased on categorical vars in table
Thanks!! Now I tried Data.DV = zeros(27,1) for x = 1:27 if strcmp(Data(x).BS, 'Total assets') Data.DV(x) =1; ...

casi 3 años ago | 0

Question

Dummy Variable ased on categorical vars in table
hi everyone! I'm tying to create a dummy variable in a table based on two categorical variables. My table contains numerical a...

casi 3 años ago | 3 answers | 0

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Question

What is a simple code for the chapman cycle involving only hydrogen and oxygen.This code should produce a curve but it only produces straight lines?
function Chapman_cycle y0= [2e17 1e-6 5e12]; tspan=[0 100]; %tspan=[0,1.0e-5,1.0e-3,0.1,0.5,1,2,4,6,8,10,20,30,40,50,...

más de 3 años ago | 1 answer | 0

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Question

How do I display individual values from an if statement in a messgae?
Ok bear with me. I am trying to write a script that gives the root to a function using the bisection method. However it is no...

más de 3 años ago | 1 answer | 0

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Question

How do I count how many iterations my root is in a smaller interval?
In my code I need to display in the command line how many of the iterations my root was in the smaller interval. I am not entire...

más de 3 años ago | 1 answer | 0

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Question

Subscript Indices must either be real positive intergers or logicals - not sure where i'm going wrong.
I am trying to call the RK4 function below in order to find the second initial value for my main function. However it gets stuck...

más de 3 años ago | 1 answer | 0

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Question

how can I remove the background this image , I do thresholding but I can't remove the background( I want only the dark object and determine their location) ?

más de 3 años ago | 1 answer | 0

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Question

Hello can someone show me a simple code to show the earths orbit around the sun using ordinary differential equations.
function Earthsorbit e=2; y0=[1 2*pi 0 -pi]; tspan=[0, 10]; options = odeset('RelTol',1e-4,'AbsTol',1e-4); ...

más de 3 años ago | 2 answers | 0

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Question

Creating a matrix where the entry in the second column is (weakly) less than the entry in the first column
Hello, I would like to create a matrix where the entry in the second column is less than the entry in the first column: ...

alrededor de 4 años ago | 1 answer | 0