- #1

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## Homework Statement

I am very confused over how matlab knows which variables are changeable variables in ode45.

## Homework Equations

//## The Attempt at a Solution

My input is p

Earlier have defined;

a = 1;

k = 1;

w = 1/3;

Then I want to figure out adot and adoubledot from these.

adot = (a)*(p - k/a)^(-1/2);

adoubledot = (a/2)*(p + 3*w*p);

Suddenly realised that I have no idea why matlab would let "a" change but not let "p" and "k" change...

Is there a way to tell matlab that one of the variables is changing in time and the others aren't?