derivs_Schrodinger()

void derivs_Schrodinger(double x, double y[], double dydx[],
                        int k, double T[], double r[], double dr[], int N)

Output:

• dydx[]: value of $\frac{d}{dx} \vec y$, defined as below

Input:

• x: value of independent variable (not used)
• y[]: y[1]=$\Psi(r)$, y[2]=$\Psi'(r)$
• k: integer index of arrays corresponding to x (x=k/N), so that r(x)=r[k], etc.
• T[]: kinetic energy, T[k]=T(r[k])
• r[], dr[], N: standard grid information

Include a function of the form above in the file ``physics.c'' before the code for schint(), where

$$\frac{d}{dx} \vec y = \left(\begin{array}{c} \Psi \\ \Psi'\... ...) \\ -2 T(r(x)) \Psi(r(x)) \frac{dr}{dx}(x)\end{array}\right).$$