Community Profile

# Bobby Fischer

Last seen: 8 maanden ago Active since 2020

All

#### Content Feed

View by

Question

Surf command to plot simple surface
Hi what is happening here: close all x = -1 : 0.1 : 5; y = x; [X, Y] = meshgrid(x,y); Z = 2*X - X*Y + 2*Y; surf(X, Y, Z)...

ongeveer een jaar ago | 1 answer | 0

### 1

Question

Boundary value problem solvers in Matlab accept mixed boundary conditions, neumann boundary conditions?
Boundary value problem solvers in Matlab accept mixed boundary conditions, neumann boundary conditions?

ongeveer een jaar ago | 0 answers | 0

### 0

Question

simple fmincon problem, optimization toolbox
I have an optimization problem in that Matlab solves depending on the initial value given. First, I give X0 = [10 10 10] as the...

ongeveer een jaar ago | 1 answer | 0

### 1

Question

Show stats in bvp4c
Hi, I would like to see the stats, like the number of iterations. I have 'Stats' 'on' but doesn't show anything. Thanks for yo...

ongeveer een jaar ago | 1 answer | 0

### 1

Question

bvp4c's guess for boundary conditions
Hi. I'd like to know why the initial guess for the solution shouldn't always be the boundary conditions themselves. That is, why...

meer dan een jaar ago | 1 answer | 0

### 1

Question

Light direction in surfl
Hi, I don't understand why it is not centered. x = -1:.1:1; y = -1:.1:1; [X,Y] = meshgrid(x,y); z = X.^2 + Y.^2; surfl(x,y...

meer dan een jaar ago | 1 answer | 0

### 1

Plot 2D data colormap
This could help: x = -3 + 6*rand(50,1); y = -3 + 6*rand(50,1); v = sin(x).^4 .* cos(y); F = scatteredInterpolant(x,y,v); ...

meer dan een jaar ago | 0

Question

Anomaly with comments and rating in one file in File Exchange.
https://www.mathworks.com/matlabcentral/fileexchange/85900-seawater-density-from-salinity-temperature-and-pressure I posted thi...

bijna 2 jaar ago | 1 answer | 0

### 1

Question

Function 'subs' different output for a (similar?) input
clc syms F(t) F(t)=[-5*cos(2*t) -5*sin(2*t) 3*exp(2*t); -2*(cos(2*t)+sin(2*t)) 2*(cos(2*t)-sin(2*t)) 0; cos(2*t) sin...

bijna 2 jaar ago | 1 answer | 0

### 1

Solved

Select every other element of a vector
Write a function which returns every other element of the vector passed in. That is, it returns the all odd-numbered elements, s...

bijna 2 jaar ago

Solved

Generate a vector like 1,2,2,3,3,3,4,4,4,4
Generate a vector like 1,2,2,3,3,3,4,4,4,4 So if n = 3, then return [1 2 2 3 3 3] And if n = 5, then return [1 2 2...

bijna 2 jaar ago

Solved

Make the vector [1 2 3 4 5 6 7 8 9 10]
In MATLAB, you create a vector by enclosing the elements in square brackets like so: x = [1 2 3 4] Commas are optional, s...

bijna 2 jaar ago

Submitted

Fourier series finite expansion.
I did this to learn grosso modo how Fourier series work.

Question

Now I get this message when I open Matlab: ---------------------------------------------------- Your MATLAB license will ...

bijna 2 jaar ago | 1 answer | 0

### 1

confusion on a new schema for solving ode
Hello, function euler1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clc clear tic delta_q=1e-4; q1=0;...

bijna 2 jaar ago | 0

| accepted

Solved

Finding Perfect Squares
Given a vector of numbers, return true if one of the numbers is a square of one of the other numbers. Otherwise return false. E...

bijna 2 jaar ago

Solved

Return area of square
Side of square=input=a Area=output=b

bijna 2 jaar ago

Solved

Maximum value in a matrix
Find the maximum value in the given matrix. For example, if A = [1 2 3; 4 7 8; 0 9 1]; then the answer is 9.

bijna 2 jaar ago

plot log with factor 20
Hello a=1.03; h=(a^200-a^20)/9; ypoints=a^(20):h:a^200; xpoints=log(ypoints)./log(a); figure(1) close(1) figure(1) h...

bijna 2 jaar ago | 1

| accepted

Question

Discrepancy with easy ODE.
Hello, don't know why the discrepancy. function fcno y0=linspace(0,2,20); t0=linspace(0,3,100); figure(1) close(1) figure...

bijna 2 jaar ago | 1 answer | 0

### 1

Solved

Find the sum of all the numbers of the input vector
Find the sum of all the numbers of the input vector x. Examples: Input x = [1 2 3 5] Output y is 11 Input x ...

bijna 2 jaar ago

Solved

Given a and b, return the sum a+b in c.

bijna 2 jaar ago

How to solve 'Index exceeds matrix dimensions.' error?
Hi, there was a bunch of things to correct. Don't know if the result still has some value because I don't know what I was workin...

bijna 2 jaar ago | 0

Question

ode45 fail with pendulum
Hello. I have proof that in my machine the pendulum goes all the way around, contradicting reality. Any thoughts? -------------...

bijna 2 jaar ago | 1 answer | 0

### 1

How can i plot surfaces for a recursive function?
Hi, I have written this code. Is this what you meant? function []=bobby_98(n) lon=20; x=linspace(-1,1,lon); y=x; z=zeros(l...

meer dan 2 jaar ago | 0

Question

Start new session everytime
Hi, I would like Matlab to open with the command window and no editor tabs open. That is, if I had editor tabs open in my last...

meer dan 2 jaar ago | 0 answers | 0

### 0

Question

Hi, How can I change the transparency of the rectangles? function [I]=bobby_85(n) % n=30; n=300; p=1; h=1/(n-1); I=0; x...

meer dan 2 jaar ago | 0 answers | 0