spradius 1.0.0

A spectral radius package for time-integration in solid dynamics

A spectral radius package for time-integration in solid dynamics.

spRadius is a not-so fast spectral radius computation package for Python.

Installation

Clone this repository into your system

git clone [e-mail]:amcc1996/spradius.git

and install the Python package with pip3, running the following command inside spRadius root directory, where the setup.py is located

pip3 install .

At this point, spRadius can be imported into your Python scripts and modules the usual Python-way

import spradius

Example

import matplotlib.pyplot as plt
import numpy as np

from spradius import generalised_alpha, hht, newmark


dt = np.logspace(-3, 3, num=100)

rho_newmark = newmark(dt)
rho_newmark2 = newmark(dt, beta=0.3025, gamma=0.6)
rho_hht = hht(dt, alpha=0.05)
rho_hht2 = hht(dt, alpha=0.3)
rho_gen_alpha = generalised_alpha(dt, rho_infty=0.8)
rho_gen_alpha2 = generalised_alpha(dt, rho_infty=0.2)

fig, ax = plt.subplots(
    1, 1, num="spradius example", constrained_layout=True, figsize=(6, 6)
)
ax.semilogx(
    dt,
    rho_newmark.spectral_radius,
    label=r"Newmkark $\beta=0.25$ $\gamma=0.5$",
    clip_on=True,
)
ax.semilogx(
    dt,
    rho_newmark2.spectral_radius,
    label=r"Newmkark $\beta=0.3025$ $\gamma=0.6$",
    clip_on=True,
)
ax.semilogx(
    dt, rho_hht.spectral_radius, label=r"HHT $\alpha=0.05$", clip_on=True
)
ax.semilogx(
    dt, rho_hht2.spectral_radius, label=r"HHT $\alpha=0.3$", clip_on=True
)
ax.semilogx(
    dt,
    rho_gen_alpha.spectral_radius,
    label=r"GEN-$\alpha$ $\rho_{\infty}=0.8$",
    clip_on=True,
)
ax.semilogx(
    dt,
    rho_gen_alpha2.spectral_radius,
    label=r"GEN-$\alpha$ $\rho_{\infty}=0.2$",
    clip_on=True,
)
ax.set_xlabel(r"Non-dimensional time step, $\Delta t / T_1$")
ax.set_ylabel(r"Spectral radius, $\rho$")
ax.set_xlim(dt[0], dt[-1])
ax.set_ylim(0, 1.1)
ax.legend()
ax.grid()

plt.show()

Running the tests

SymBeam tests can by run with pytest so start by installing the framework

pip3 install pytest
pip3 install pytest-cov # optional, to generate coverage reports

and launch the testing utility from spRadius root directory

make tests

The coverage reports can be generated with

make coverage

which will run the test and create the coverage information in htmlcov.

License

Copyright 2020, António Carneiro

spRadius is free and open-source software and is published MIT License.