rdeefx.spad line 345 [edit on github]
Risch differential equation, wrapper for extended version.
do_param_RDE(f, h, lg, x, lk)
solves parametric Risch differential equation, that is returns [y, [c1, ..., ck]]
such that dy/dx + n
df/dx y
+ c1
g1
+ ... cn
gn
= h
where y
is in the is in field generated by lk
and ci
are constants or "failed" if there is no solution.
do_risch_DE(f, g, x, lk)
returns [y, h, 0, b]
such that dy/dx + df/dx y = h
and b := h = g
. The equation dy/dx + df/dx y = g
has no solution in the field generated by lk
if h ~= g
(y
is a partial solution in that case).
risch_de_ext(n, f, g, x)
returns [y, h, p, b]
such that dy/dx + n df/dx y + exp(-nf)dp/dx = h
and b := h = g
. The equation dy/dx + n df/dx y = g
has no solution if h ~= g
(y
is a partial solution in that case).