def _integrand_linear(k, r, l, psfunc): return 1.0 / (2*math.pi**2) * k**2 * sphbessel.jl(l, k*r) * psfunc(k)
def _int_lin(k): return (k**2 * self.ps_vv(k) * (b1 * sphbessel.jl(l, k*x1) - f1 * sphbessel.jl_d2(l, k*x1)) * (b2 * sphbessel.jl(l, k*x2) - f2 * sphbessel.jl_d2(l, k*x2)))