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Analyzing Stability Properties

Plotting the region of absolute stability

Region of absolute stability for the optimal SSP 10-stage, 4th order Runge-Kutta method:

System Message: WARNING/2 (/home/docs/checkouts/readthedocs.org/user_builds/nodepy/checkouts/latest/doc/stability.rst, line 11)

Exception occurred in plotting stability-1 from /home/docs/checkouts/readthedocs.org/user_builds/nodepy/checkouts/latest/doc/stability.rst: Traceback (most recent call last): File “/home/docs/.pyenv/versions/3.7.3/lib/python3.7/site-packages/matplotlib/sphinxext/plot_directive.py”, line 499, in run_code exec(code, ns) File “<string>”, line 1, in <module> ModuleNotFoundError: No module named ‘nodepy’

from nodepy.runge_kutta_method import *
ssp104=loadRKM('SSP104')
ssp104.plot_stability_region(bounds=[-15,1,-10,10])

(Source code)

Region of absolute stability for the 3-step Adams-Moulton method:

System Message: WARNING/2 (/home/docs/checkouts/readthedocs.org/user_builds/nodepy/checkouts/latest/doc/stability.rst, line 23)

Exception occurred in plotting stability-2 from /home/docs/checkouts/readthedocs.org/user_builds/nodepy/checkouts/latest/doc/stability.rst: Traceback (most recent call last): File “/home/docs/.pyenv/versions/3.7.3/lib/python3.7/site-packages/matplotlib/sphinxext/plot_directive.py”, line 499, in run_code exec(code, ns) File “<string>”, line 1, in <module> ModuleNotFoundError: No module named ‘nodepy’

from nodepy.linear_multistep_method import *
am3=Adams_Moulton(3)
am3.plot_stability_region()

(Source code)

Plotting the order star

Order star for the optimal SSP 10-stage, 4th order Runge-Kutta method:

System Message: WARNING/2 (/home/docs/checkouts/readthedocs.org/user_builds/nodepy/checkouts/latest/doc/stability.rst, line 41)

Exception occurred in plotting stability-3 from /home/docs/checkouts/readthedocs.org/user_builds/nodepy/checkouts/latest/doc/stability.rst: Traceback (most recent call last): File “/home/docs/.pyenv/versions/3.7.3/lib/python3.7/site-packages/matplotlib/sphinxext/plot_directive.py”, line 499, in run_code exec(code, ns) File “<string>”, line 1, in <module> ModuleNotFoundError: No module named ‘nodepy’

from nodepy.runge_kutta_method import *
ssp104=loadRKM('SSP104')
ssp104.plot_order_star()

(Source code)

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