from sympy import *
init_printing()
from IPython.display import display
var('fv pv pmt np ir')
vt = (fv,pv,pmt,np)
eq = Eq(fv,(-ir*pv*(ir + 1)**np - pmt*(ir + 1)**np + pmt)/ir)
fdic = {}
for v in vt:
    sol = Eq(v,solve(eq,v)[0])
    display(sol)
    vl = list(vt)+[ir]
    vl.remove(v)
    fdic[v] = Lambda(vl,sol.rhs)

$$fv=\frac{1}{ir}(-irpv{(ir+1)}^{np}-pmt{(ir+1)}^{np}+pmt)$$

$$pv=\frac{1}{ir}{(ir+1)}^{-np}(-fvir-pmt{(ir+1)}^{np}+pmt)$$

$$pmt=-\frac{ir(fv+pv{(ir+1)}^{np})}{{(ir+1)}^{np}-1}$$

$$np=\frac{\log \left(\frac{-fvir+pmt}{irpv+pmt}\right)}{\log (ir+1)}$$

fvr = fdic[fv](0,-100,120,.01)
pvr = fdic[pv](fvr,-100,120,.01)
pmtr = fdic[pmt](fvr,0,120,.01)
npr = fdic[np](fvr,0,-100,.01)
print("%.2f %.2f %.2f %.2f" %  (fvr,pvr,pmtr,npr))

23003.87 -0.00 -100.00 120.00