Answered
generating random no. between -pi to pi
See the example Random Numbers within Specified Intervals under https://de.mathworks.com/help/matlab/ref/rand.html

4 years ago | 1

Answered
How can I solve 4 simultaneous equations ?
You might want to test fsolve and lsqnonlin with different initial guesses for the parameters, but I doubt you will find a sol...

4 years ago | 0

| accepted

Answered
BVP4C for solving an 3rd order ODE
tmesh = linspace(0,10,100); solinit = bvpinit(tmesh, [0 1 0]); sol = bvp4c(@odefun, @bcfcn, solinit); plot(sol.x, sol.y) f...

4 years ago | 1

| accepted

Answered
Find the polar representation of (𝑖 − √3 )
https://de.mathworks.com/help/matlab/ref/cart2pol.html

4 years ago | 0

Answered
Help with time dependent ODE with a piece-wise component that needs to mirror a convolution integral
tspan1 = 0:0.01:0.2; odefcn1 = @(t,y) [y(2); -(1500.*y(1) - 1500.*(2.5.*t))./5]; y0_1 = 0; ydot0_1 = 0; ics1 = [y0_1 ydot0_1...

4 years ago | 0

Answered
I need help to execute a triple integral
You still didn't get the point. Look at the documentation of integral3: q = integral3(fun,xmin,xmax,ymin,ymax,zmin,zmax) appro...

4 years ago | 1

| accepted

Answered
How to solve differential equation including derivative of eigenvalue of tensor?
A third variante of the code also seems to work under MATLAB ( for high values of the integration tolerances :-) ) syms s A = ...

4 years ago | 1

| accepted

Answered
The (x,y) coordinates of a certain object as a function of time t are given by x(t) = 5t - 10; and y(t) = 25t2 – 120 t + 144, for 0 ≤ t ≤ 4. 1)
syms t x = 5*t-10; y = 25*t^2-120*t+144; distance_squared = x^2+y^2; d_distance_squared_dt = diff(distance_squared,t); time...

4 years ago | 1

| accepted

Answered
plotting a graph in a range
R = 2.303 * 8.314; F = 96500; ratio = @(T,eqv,z) exp(eqv*(z*F)./(R*T)); T = 283:313; plot(T, ratio(T,-0.06,1))

4 years ago | 0

| accepted

Answered
Array indices must be positive integers or logical values.
Everywhere where you want to multiply two quantities, you must set the multiplication sign. Something like r1 = k1(xch4*xh2o*P...

4 years ago | 0

Answered
How do I solve a triple integral with one integral limit in function of another variable
beta1= 1.72; mo1=5; rmin1=10; rmax1 = 20; mmax1 = 10; fun=@(r,m,s) r.*exp(-(s.^2/2 + beta1*(m-mo1)))./sqrt(r.^2-rmin1); z...

4 years ago | 1

Answered
2D Temperature distribution from 1D temperature distribution T(x)
x_position = [0.05; 0.0625; 0.075; 0.0875; 0.10; 0.1125; 0.125; 0.1375; 0.15; 0.1625; 0.175; 0.1875; 0.2; 0.2125; 0.225; 0.2375...

4 years ago | 0

| accepted

Answered
How to solve differential equation including derivative of eigenvalue of tensor?
Here is a numerical code to solve your problem. It's risky to use this approach since - as Walter Roberson noted - the ordering...

4 years ago | 1

Answered
y(k + 2) = 0.25y(k), y(0) = 0, y(1) =1 (b). Write a Matlab script that solves y(k) pointwise for k =0,1,2,…,10. Ruun the program and verify that the solution is in accordance
Initialize y(1) = 0, y(2) = 1 and use a for-loop to calculate y(k+2) starting with k = 1 and ending with k = 9.

4 years ago | 0

Answered
How to solve coupled second order ODE?
b = 0.1; fun = @(t,y)[y(2);-b*y(2)*sqrt(y(2)^2+y(4)^2);y(4);-b*y(4)*sqrt(y(2)^2+y(4)^2)]; y0 = [0;44.5;80;0]; tspan = [0,10];...

4 years ago | 0

Answered
Getting the summation of a series
h=[ 1 3 5 7 9 11 13 15] ; ah = [35.8577 -6.2962 -1.2855 3.9251 -3.8197 2.2690 -0.4077 -0.9397 ]; alpha = lins...

4 years ago | 1

| accepted

Answered
Using fminsearch() for MSD system
p0 = [50 400]; p = fminsearch(@fun,p0) function objective = fun(p) k2 = p(1); c2 = p(2); %tspan = [0,0.3]; %observing sys...

4 years ago | 0

| accepted

Answered
Create a unit vector from two locations?
is this correct? No. MTH2 = [0.472 1.364 0.06] CoM = [0.471 1.147 0.903] UnitVector = (CoM - MTH2) / norm(CoM - MTH2)

4 years ago | 0

Answered
how to use derivative of function using gradient?
Forget about y(13) and use dydz(2) = y(3); %Specific mass balance (CH4) dydz(3) = ((y(1)*y(3))+(dens_cat_weighted*r_CH4))/(D_m...

4 years ago | 1

Answered
How to solve differential equation including derivative of eigenvalue of tensor?
See if it works. I cannot test it. syms s A = sym('A',[3 3]); % Define characteristic polynomial determinant = det(A-s*eye(3...

4 years ago | 1

Answered
Solving a numeric equation matlab shows results with up to 32 decimals. How can I get this for the operation below for Exmpl? format longE for Exmpl. allows only 16 digits.
digits(100) vpa(sqrt(sym('3')))

4 years ago | 0

| accepted

Answered
Minimalization problem LinearConstraint and conjugate gradient optimizer
According to the Python code, F is maximized, not minimized. Change in the below code if appropriate. M = [0.170543 0.327434 0....

4 years ago | 0

| accepted

Answered
Performing Chi Square Test
Source: https://de.mathworks.com/matlabcentral/answers/96572-how-can-i-perform-a-chi-square-test-to-determine-how-statistically...

4 years ago | 1

| accepted

Answered
Substitute symbolic matrices into numerical matrices
Do you know Cramer's rule ? A = sym('A',[3 3]); b = sym('b',[3 1]); x = sym('x',[3 1]); sol = solve(A*x==b,x) And now pleas...

4 years ago | 0

Answered
System of Nonlinear Equations are failing to be solved
In my opinion, it should be eq1 = C_arg + P_arg == pi-phi_m*pi/180; instead of eq1 = C_arg + P_arg == pi-phi_m*180/pi; (see ...

4 years ago | 1

| accepted

Answered
Force a starting point on exponential graph
You must normalize to time = 0, not time = 24.4. The initial mass is the key, not the mass when already 24.4 (whatever) have pa...

4 years ago | 0

Answered
How do I write the below code in efficient way in MATLAB?
Q = [16,32,64,128,256,512,1024]; VEC=[0.2380 0.2380 0.2380 0.2380 0.2380 0.2380 0.2380 1.1898 1....

4 years ago | 0

| accepted

Answered
Please help me in plotting the following functions.
Limits of Euler's beta function are 0 and 1, not a and b. So C_m,i^nu = beta(i*nu+3,(m-i)*nu)/beta(i*nu,(m-i)*nu) + 2 and th...

4 years ago | 1

Answered
How to plot 4 curves with different constants?
y = @(C,x) (C-x)./(1+x.^2); C = [1 2 3 4].'; x = -2:0.1:2; plot(x,y(C,x))

4 years ago | 0

Answered
Use of 'ArrayValued' in Matlab numerical integration
f = @(x) 5*ones(size(x)); integral(f,0,2)

4 years ago | 1