Question

Matlab gives wrong solution of a nonlinear system of equations.

I had bigger (6 equations) system of ODE and reduced it to the follwing system to check if we cand find equilibruim points . ...

12 days ago | 2 answers | 0

Question

Solve a system of nonlinear equations with conditions

I have the follwing system of equation which I want to solve . How I will put conditions that all parameters shoud be positive a...

29 days ago | 1 answer | 0

Question

Error while solving a coupled system of ODE

I am trying to solve a system of 6 coupled ODE my function works but I dont know why calling ode45 doesnt work. My function i...

2 months ago | 1 answer | 0

Question

Solve and plot the phase portrait for van der pol ODE with time dependent term

I want to solve this system of ode by ode45 and then plot the x1 and x2 with t and phase portrait later but I got error which i ...

10 months ago | 1 answer | 0

Question

Draw the vector field and eigenvectors in the phase portrait for Van der Pol ODE

I have the follwing system which represent the Van der Pol oscillator with the inital condition and parameters are given. I draw...

10 months ago | 1 answer | 0

Question

Gauss Siedel for solving a linear system of equations

Hi , *I want to fix this code for Gauss Siedel method for solving a linear system of equations* Here we are using some val...

2 years ago | 0 answers | 0

Question

3 dimentions matrix Creation

Hei, I have this matrix A=[4 -1 1;4 -8 1;-2 1 5] And I want to add a third dinention (page) to it with only one elem...

2 years ago | 1 answer | 0

Question

Compute the partial derivative numerically

Hi, I want to compute the first and second partial derivative with respect to x, y for this function x0=0 y0=0 x=[-1:...

2 years ago | 1 answer | 0

Question

find the position of en element if you have the increment

How i will find mathematically what is the position of the element correspounding z=-2 it is 21 but I cant find it mathematicall...

2 years ago | 2 answers | 0

Question

Putting a label on the colorbar in imagesc plot

Hello helpers, How I will put a label on the colorbar in the plot to show what it is actually representing ,there is nothing ab...

2 years ago | 1 answer | 0

Question

How I will change the line widith for to function in the same plot comand

Hello, How I will change the line width for two functions in the same plot command? or I will need to do it in a separate com...

2 years ago | 1 answer | 0

Question

plane y=x

Hei , I want to drow this planes y=x,z=x,z=y in 3D using fsurf but dont know fow to set the function?

2 years ago | 1 answer | 0

Question

Using greek letters as variables and as subscript in Matlab

I want to write two things : * first B and puttings theta as letter not word as subscripts * second : using lambda or other...

2 years ago | 1 answer | 1

Question

Using a variable as both output and input and writing a condition in a function

*Hei , I have this function* function [lambda, lambdap,phip] = Palaeomagfun(I ,D,lambda,lambdax,phix ) lambda=atan...

2 years ago | 1 answer | 0

Question

Stop some outputs of a function

%I have this function function [ B,H,Z,I ] = magfun( lambda ) r=6371*10^3 ; %in m u0=4*pi*10^-7 ; %in kg m A^-2 S^-2 ...

2 years ago | 1 answer | 0

Question

Using condition in Function

Hei. I have this script: %% Problem 3 clear all %a) %DATA for Nazca-Pacific o1=13.6*10^-7 l1=55.6 p...

2 years ago | 1 answer | 0

Question

long title problem printing

Hei. I have written a long title for a plot but not all of it appears when saving it as pdf! any idea to fix this?

2 years ago | 1 answer | 0

Question

Plot a cyinder with height from one value to another

I want to plot a cylinder with height that goes from -4 to 4 and radius 2?

2 years ago | 1 answer | 0

Question

USING FOR LOOP TO PLOT SEVERAL LINES

L=[4:2:20]; %X coordintates for reflaction point x3=L/2; %Y coordinates for reflection point IS -5 %X coordinate for ...

2 years ago | 1 answer | 0

Question

plot line segments on the same plot

I have 3 lines y=0,y=-6,y=-14 and have this points in the y=0 xs =[10.9412 17.6187 32.3200 77.3532] ys=[ 0 0 0 0]...

2 years ago | 0 answers | 0

Question

Compute double sum or double integral throug sum

x=[-20:0.2:10]; y=[-10:0.2:5]; u2=-3*exp(-sqrt(x.^2+y.^2)/2) I want to sum this function from y=1 to the number of el...

2 years ago | 2 answers | 0

Question

Matlab and memory use

Hi, How I can compute how much RAM memory this matrix rand(500,500) take?

2 years ago | 2 answers | 0

Question

Position of an element in a vector

Hi,I want to find the position not value of an element of a vector that meet equal a number, I have this vector z=[0:-0.01:-16]...

2 years ago | 4 answers | 1

Question

plot a cube with to planes in on figure

I have a question about a tipple integral but it was difficult to visualize the integration region which is part of the cub 0<...

2 years ago | 0 answers | 0

Question

TABLE OF 2 ROWS AND 12 COLUMNS

Hi,I want to make a TABLE OF 2 ROWS AND 12 COLUMNS WITH YEAR IN THE FIRST ROW AND NUMBER OF EARTHQUAKES IN THE SECOND ROW. ...

2 years ago | 2 answers | 0

Question

Improve my graph in matlab

Hi, I have drawn this graph but i want to improve it. It is rays that goes from one point to get reflected and come back to a po...

2 years ago | 1 answer | 0

Question

Intersection between a sphere x^2+y^2+z^2 =6 and paraboloid z=x^2+y^2

I want to draw both sphere x^2+y^2+z^2=6 and paraboloid z=x^2+y^2 in 3D to determine the integration region that is the solid re...

2 years ago | 1 answer | 0

Question

For loop comand use

Hi,I want to compute the sum 2 + 4 + 6 + 8 + 10 + : : : + 100 by using For loop . Can anyone here thankfully help me out?

2 years ago | 1 answer | 0

Question

bar and histograms for categorical data

I have this vector and std =[ 0.4041 0.7670 1.0682 0.6582 0.0475] and these lyer=categoris [{'crust','upper mantle',...

2 years ago | 1 answer | 0