Quick Start¶
My first program¶
If you have successfully installed desolver following the installation guide here you will be able to test it with the following script.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 | import desolver as de
import desolver.backend as D
@de.rhs_prettifier(
equ_repr="[vx, -k*x/m]",
md_repr=r"""
$$
\frac{dx}{dt} = \begin{bmatrix}
0 & 1 \\
-\frac{k}{m} & 0
\end{bmatrix} \cdot \begin{bmatrix}x \\ v_x\end{bmatrix}
$$
"""
)
def rhs(t, state, k, m, **kwargs):
return D.array([[0.0, 1.0], [-k/m, 0.0]])@state
y_init = D.array([1., 0.])
a = de.OdeSystem(rhs, y0=y_init, dense_output=True, t=(0, 2*D.pi), dt=0.01, rtol=1e-9, atol=1e-9, constants=dict(k=1.0, m=1.0))
print(a)
a.integrate()
print(a)
print("If the integration was successful and correct, a[0].y and a[-1].y should be near identical.")
print("a[0].y = {}".format(a[0].y))
print("a[-1].y = {}".format(a[-1].y))
print("Maximum difference from initial state after one oscillation cycle: {}".format(D.max(D.abs(a[0].y-a[-1].y))))
|
Place it into a getting_started.py text file and run it with
python getting_started.py
This script shows the numerical integration of a Hooke’s Law spring (harmonic oscillator) for a single cycle.
We recommend the use of Jupyter or ipython to enjoy desolver the most.