Alan Stevens
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Awarded to Alan Stevens on 06 Sep 2020
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Awarded to Alan Stevens on 25 May 2020
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已回答
Function g Returns Only 2 Values Instead of Array - Vectorized Operation Issue in MATLAB
You have g as a function of x2, but x2 doesn't appear on the right-hand side!
Function g Returns Only 2 Values Instead of Array - Vectorized Operation Issue in MATLAB
You have g as a function of x2, but x2 doesn't appear on the right-hand side!
2 days 前 | 0
| 已接受
已回答
Solve for x with given equation
Look up the help on function fzero. And don't forget that Matlab doesn't recognise implicit multiplication. x(...) should...
Solve for x with given equation
Look up the help on function fzero. And don't forget that Matlab doesn't recognise implicit multiplication. x(...) should...
4 days 前 | 0
已回答
power method with rayleigh coeff
Make sure you call the function with the arguments in the same order as those defined in the function! A=[4 1 -1 0;1 3 -1 0;-1 ...
power method with rayleigh coeff
Make sure you call the function with the arguments in the same order as those defined in the function! A=[4 1 -1 0;1 3 -1 0;-1 ...
5 days 前 | 0
| 已接受
已回答
Fill area between two vertical curves
Like this: value = [186.7646 198.4115 191.1406 180.8430 175.7136 ... 167.7459 151.2865 144.5964 139.8148 139.4305 188.2865 204...
Fill area between two vertical curves
Like this: value = [186.7646 198.4115 191.1406 180.8430 175.7136 ... 167.7459 151.2865 144.5964 139.8148 139.4305 188.2865 204...
24 days 前 | 2
| 已接受
已回答
Simplificar el resultado como valor numerico
Why not simply: p1=[2;3] ; x0_1=@(theta) [cos(theta); sin(theta)]; % =[x1*x0; x1*y0] y0_1=@(theta)[-sin(theta); cos(theta)];...
Simplificar el resultado como valor numerico
Why not simply: p1=[2;3] ; x0_1=@(theta) [cos(theta); sin(theta)]; % =[x1*x0; x1*y0] y0_1=@(theta)[-sin(theta); cos(theta)];...
28 days 前 | 1
已回答
Optimizing code for HAC Weight matrix generation - How to be faster?
Try replacing the loops with something like this: i = (1:size(Weight_correlation,1))'; j = 1:size(Weight_correlation,2); c = ...
Optimizing code for HAC Weight matrix generation - How to be faster?
Try replacing the loops with something like this: i = (1:size(Weight_correlation,1))'; j = 1:size(Weight_correlation,2); c = ...
1 month 前 | 0
已回答
How to a create a label at the bottom of a vertical line?
Like this? x = linspace(0,6,100); y = exp(x); plot(x,y) xline(4.5,'-',{'Acceptable','Limit'}, 'LabelVerticalAlignment', 'bot...
How to a create a label at the bottom of a vertical line?
Like this? x = linspace(0,6,100); y = exp(x); plot(x,y) xline(4.5,'-',{'Acceptable','Limit'}, 'LabelVerticalAlignment', 'bot...
1 month 前 | 0
| 已接受
已回答
Secant method Nan Error
You haven't updated error in your while loop. Try including something like error = abs(X0-X1);
Secant method Nan Error
You haven't updated error in your while loop. Try including something like error = abs(X0-X1);
1 month 前 | 0
| 已接受
已回答
Function error in ODEs RK4 method, solving 6 unknowns
It works for me (I've commented out the fprint statements in the code below - but it works with them in!): global CDin psi thet...
Function error in ODEs RK4 method, solving 6 unknowns
It works for me (I've commented out the fprint statements in the code below - but it works with them in!): global CDin psi thet...
1 month 前 | 0
| 已接受
已回答
I keep getting the error using '/'.
Try mu_ratio=(1-(vol_frac(c,1)/0.605).*((particle_ratio(c,1)).^1.2)).^(-1.5125); Notice the dots! .* .^ Difficult to be...
I keep getting the error using '/'.
Try mu_ratio=(1-(vol_frac(c,1)/0.605).*((particle_ratio(c,1)).^1.2)).^(-1.5125); Notice the dots! .* .^ Difficult to be...
1 month 前 | 0
已回答
Plateau followed by one phase decay
Like this? x = 0:0.5:20; % time in seconds Y0 = -0.6; % signal baseline value Plateau = -1; % singnal plateu after trigger/st...
Plateau followed by one phase decay
Like this? x = 0:0.5:20; % time in seconds Y0 = -0.6; % signal baseline value Plateau = -1; % singnal plateu after trigger/st...
2 months 前 | 1
| 已接受
已回答
Radiation view factor using Monte Carlo
I think you probably need cos(theta), rather than theta, to be linearly spaced.
Radiation view factor using Monte Carlo
I think you probably need cos(theta), rather than theta, to be linearly spaced.
2 months 前 | 0
已回答
How to fix a syntax in the oscillator's plot code?
Like this (both x_1 and x_2 are contained in y) T0 = 10; omega0 = 1; M = 1; F = 1; x_1 = 0; x_2 = 0; x_0 = [x_1 x_2]; ts...
How to fix a syntax in the oscillator's plot code?
Like this (both x_1 and x_2 are contained in y) T0 = 10; omega0 = 1; M = 1; F = 1; x_1 = 0; x_2 = 0; x_0 = [x_1 x_2]; ts...
2 months 前 | 0
| 已接受
已回答
ODE45has long runtime and graph will not plot
Here's my attempt to make sense of your equations tauspan = 0:100:10000; % p0 = [0.5 0.5 0 0]; % dp1dt = -rf + rr % dp2...
ODE45has long runtime and graph will not plot
Here's my attempt to make sense of your equations tauspan = 0:100:10000; % p0 = [0.5 0.5 0 0]; % dp1dt = -rf + rr % dp2...
3 months 前 | 0
已回答
Two graphs in the same plot, why?
Something like this data = xlsread('sunHoursInTrollhattan.xlsx'); mins = data(:,1)*60 + data(:,2); plot(1:12, mins,'o'),grid ...
Two graphs in the same plot, why?
Something like this data = xlsread('sunHoursInTrollhattan.xlsx'); mins = data(:,1)*60 + data(:,2); plot(1:12, mins,'o'),grid ...
3 months 前 | 0
| 已接受
已回答
Two graphs in the same plot, why?
You have the hours as one plot and the minutes as the other! Turn the data into all minutes, or all hours first.
Two graphs in the same plot, why?
You have the hours as one plot and the minutes as the other! Turn the data into all minutes, or all hours first.
3 months 前 | 0
已回答
Could anyone help me in fixing the problem in my code for solving the initial value problem numerically: y'=y^2, y(0)=1?
Here's an attempt using fminsearch. I don't know anything about the Obreschkoff method, so couldn't say if your equations are...
Could anyone help me in fixing the problem in my code for solving the initial value problem numerically: y'=y^2, y(0)=1?
Here's an attempt using fminsearch. I don't know anything about the Obreschkoff method, so couldn't say if your equations are...
3 months 前 | 0
| 已接受
已回答
I get this message(Attempted to access F(5); index out of bounds because numel(F)=4.) when I run the code below..
In fsode you try to use F(7) when calculating F(5), before you have calculated F(7)!
I get this message(Attempted to access F(5); index out of bounds because numel(F)=4.) when I run the code below..
In fsode you try to use F(7) when calculating F(5), before you have calculated F(7)!
3 months 前 | 1
| 已接受
已回答
Laser Rate Equation Modelling
Like this? (Look at lines 27, 28 and 38) %Script % Define model parameters temperature = 25; wavelength = 1.312e...
Laser Rate Equation Modelling
Like this? (Look at lines 27, 28 and 38) %Script % Define model parameters temperature = 25; wavelength = 1.312e...
3 months 前 | 0
已回答
Determine the coordinates of the nodes forming the outermost circle
Here's an alternative way: nodes = importdata("nodes.mat"); figure plot3(nodes(:,1),nodes(:,2),nodes(:,3),'b.','Markersize',1...
Determine the coordinates of the nodes forming the outermost circle
Here's an alternative way: nodes = importdata("nodes.mat"); figure plot3(nodes(:,1),nodes(:,2),nodes(:,3),'b.','Markersize',1...
3 months 前 | 0
已回答
Problem with fitting a loglog plot
polyfit doesn't like the log of zero. One option is to remove the first row of the data: data_exp_high = load("data_Q_1e-8.txt...
Problem with fitting a loglog plot
polyfit doesn't like the log of zero. One option is to remove the first row of the data: data_exp_high = load("data_Q_1e-8.txt...
3 months 前 | 0
已回答
Index in position 2 exceeds array bounds (Index must not exceed 1) errors?
N0 is a 4x1 vector, but you call it with two indices in the for loop! Turn N(1,j) into N(1) and similarly for the other calls t...
Index in position 2 exceeds array bounds (Index must not exceed 1) errors?
N0 is a 4x1 vector, but you call it with two indices in the for loop! Turn N(1,j) into N(1) and similarly for the other calls t...
3 months 前 | 0
| 已接受
已回答
How do I solve this ODE system where there exists derivatives in both sides?
You can separate the terms as follows:
How do I solve this ODE system where there exists derivatives in both sides?
You can separate the terms as follows:
3 months 前 | 0
已回答
why am i getting grey figure box can someone fix please
Making some assumptions about your function pendulumODE, I think the following is more like what you expect to see: % Constants...
why am i getting grey figure box can someone fix please
Making some assumptions about your function pendulumODE, I think the following is more like what you expect to see: % Constants...
3 months 前 | 0
已回答
Algae growing, concentration curve problem
Increase nt to 10000 and it works just fine for T = 20000.
Algae growing, concentration curve problem
Increase nt to 10000 and it works just fine for T = 20000.
3 months 前 | 0
已回答
Error ''Array indices must be positive integers or logical values.'' when putting interval of 0.01 in a for loop
More like this: k = 0:0.1:2; n = numel(k); for i = 1:n x(i) = k(i); y(i) = k(i)*k(i) + 3*k(i) - 4; end plot(x,y...
Error ''Array indices must be positive integers or logical values.'' when putting interval of 0.01 in a for loop
More like this: k = 0:0.1:2; n = numel(k); for i = 1:n x(i) = k(i); y(i) = k(i)*k(i) + 3*k(i) - 4; end plot(x,y...
4 months 前 | 0
已回答
Trying to code from Polymath
Like this for example (I'll leave you to extract the numerical values): Wspan = [0 2]; % Integration range % Initial valu...
Trying to code from Polymath
Like this for example (I'll leave you to extract the numerical values): Wspan = [0 2]; % Integration range % Initial valu...
4 months 前 | 0
已回答
Unable to solve differential equation with finite difference method
Should be more like this I think: b = 0.02; m = 80; L = 0.7; g = 9.81; J = m * L^2/3; a = 0; bet = 2; alpha = 0; beta = 3...
Unable to solve differential equation with finite difference method
Should be more like this I think: b = 0.02; m = 80; L = 0.7; g = 9.81; J = m * L^2/3; a = 0; bet = 2; alpha = 0; beta = 3...
4 months 前 | 0
已回答
FDM using succsesive overrelaxation method,
For w1 and T1 you have w1(:,Nx1+1) = (((la*B1*dx1)/(dx2*A1))*(w2(:,2)-w2(:,1)))+w1(:,Nx1); %Continuity of shear stress ...
FDM using succsesive overrelaxation method,
For w1 and T1 you have w1(:,Nx1+1) = (((la*B1*dx1)/(dx2*A1))*(w2(:,2)-w2(:,1)))+w1(:,Nx1); %Continuity of shear stress ...
4 months 前 | 0
已回答
Solving first order ODE with initial conditions and symbolic function
You can do it numerically as follows: % input parameters Tinf=70+273.15; Ti=20+273.15; d=15e-2; r=d/2; cdepth=10/1100; Tf...
Solving first order ODE with initial conditions and symbolic function
You can do it numerically as follows: % input parameters Tinf=70+273.15; Ti=20+273.15; d=15e-2; r=d/2; cdepth=10/1100; Tf...
5 months 前 | 0
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