1.(adsbygoogle = window.adsbygoogle || []).push({});

a line in my code is something like

int(phi*x^2,0,2)

where i want phi to be a function which the user

has choosen. But how can i let the user choose a function? For numbers you can use input but how to do

it with a function?

2.

i want to solve a nonlinear system of equations in x,y.

exp(-2x)*(2*r*x-1)+1=8*pi*r^2 (1)

exp(-2x)*(2*r*y+1)-1=8*pi*r^2

Do you have to specify r before you solve the system or can you get a solution as function of r,

x=f(r) (2)

y=g(r)

?

x and y are parameters in a spherical symmetric metric and r are the radius so i guess you need a solution like (2)? But is that possible in matlab? Do you need to solve the system for many different r's and then plot the x and y as a function a r?

Thank you.

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# Matlab questions

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