Advanced: Optimizing Performance with PHOEBE

Setup

Let's first make sure we have the latest version of PHOEBE 2.1 installed. (You can comment out this line if you don't use pip for your installation or don't want to update to the latest release).



In [ ]:

    
!pip install -I "phoebe>=2.1,<2.2"



In [1]:

    
import phoebe



In [2]:

    
b = phoebe.default_binary()

Interactivity Options

When running in an interactive Python session, PHOEBE updates all constraints and runs various checks after each command. Although this is convenient, it does take some time, and it can sometimes be advantageous to disable this to save computation time.

Interactive Checks

By default, interactive checks are enabled when PHOEBE is being run in an interactive session (either an interactive python, IPython, or Jupyter notebook session), but disabled when PHOEBE is run as a script directly from the console. When enabled, PHOEBE will re-run the system checks after every single change to the bundle, raising warnings via the logger as soon as they occur.

This default behavior can be changed via phoebe.interactive_checks_on() or phoebe.interactive_checks_off(). The current value can be accessed via phoebe.conf.interactive_checks.



In [3]:

    
print(phoebe.conf.interactive_checks)









    



True



In [4]:

    
phoebe.interactive_checks_off()



In [5]:

    
print(phoebe.conf.interactive_checks)









    



False

If disabled, you can always manually run the checks via b.run_checks().



In [6]:

    
passed, msg = b.run_checks()
print(passed, msg)









    



(True, '')



In [7]:

    
b.set_value('requiv', component='primary', value=50)



In [8]:

    
passed, msg = b.run_checks()
print(passed, msg)









    



(False, 'primary is overflowing at periastron (requiv=50.0, requiv_max=2.01327517654)')

Interactive Constraints

By default, interactive constraints are always enabled in PHOEBE, unless explicitly disabled. Whenever a value is changed in the bundle that affects the value of a constrained value, that constraint is immediately executed and all applicable values updated. The ensures that all constrained values are "up-to-date".

If disabled, constraints are delayed and only executed when needed by PHOEBE (when calling run_compute, for example). This can save significant time, as each value that needs updating only needs to have its constraint executed once, instead of multiple times.

This default behavior can be changed via phoebe.interactive_constraints_on() or phoebe.interactive_constraints_off(). The current value can be accessed via phoebe.conf.interactive_constraints.

Let's first look at the default behavior with interactive constraints on.



In [9]:

    
print(phoebe.conf.interactive_constraints)









    



True



In [10]:

    
print(b.filter('mass', component='primary'))









    



ParameterSet: 2 parameters
*         mass@primary@component: 0.998813135806 solMass
         mass@primary@constraint: (39.478418 * ({sma@binary@component} ** 3.000000)) / ((({period@binary@component} ** 2.000000) * (1.000000 + {q@binary@component})) * 2942.206217504418873431859537959099)



In [11]:

    
b.set_value('sma@binary', 10)



In [12]:

    
print(b.filter('mass', component='primary'))









    



ParameterSet: 2 parameters
*         mass@primary@component: 6.70898215175 solMass
         mass@primary@constraint: (39.478418 * ({sma@binary@component} ** 3.000000)) / ((({period@binary@component} ** 2.000000) * (1.000000 + {q@binary@component})) * 2942.206217504418873431859537959099)

Note that the mass has already updated, according to the constraint, when the value of the semi-major axes was changed. If we disable interactive constraints this will not be the case.



In [13]:

    
phoebe.interactive_constraints_off()



In [14]:

    
print(phoebe.conf.interactive_constraints)









    



False



In [15]:

    
print(b.filter('mass', component='primary'))









    



ParameterSet: 2 parameters
*         mass@primary@component: 6.70898215175 solMass
         mass@primary@constraint: (39.478418 * ({sma@binary@component} ** 3.000000)) / ((({period@binary@component} ** 2.000000) * (1.000000 + {q@binary@component})) * 2942.206217504418873431859537959099)



In [16]:

    
b.set_value('sma@binary', 15)



In [17]:

    
print(b.filter('mass', component='primary'))









    



ParameterSet: 2 parameters
*         mass@primary@component: 6.70898215175 solMass
         mass@primary@constraint: (39.478418 * ({sma@binary@component} ** 3.000000)) / ((({period@binary@component} ** 2.000000) * (1.000000 + {q@binary@component})) * 2942.206217504418873431859537959099)

No need to worry though - all constraints will be run automatically before passing to the backend. If you need to access the value of a constrained parameter, you can explicitly ask for all delayed constraints to be executed via b.run_delayed_constraints().



In [18]:

    
b.run_delayed_constraints()









    Out[18]:





[<Parameter: sma=7.5 solRad | keys: description, value, quantity, default_unit, limits, visible_if, copy_for>,
 <Parameter: mass=22.6428147622 solMass | keys: description, value, quantity, default_unit, limits, visible_if, copy_for>,
 <Parameter: mass=22.6428147622 solMass | keys: description, value, quantity, default_unit, limits, visible_if, copy_for>,
 <Parameter: requiv_max=5.69794861284 solRad | keys: description, value, quantity, default_unit, limits, visible_if, copy_for>,
 <Parameter: sma=7.5 solRad | keys: description, value, quantity, default_unit, limits, visible_if, copy_for>,
 <Parameter: asini=15.0 solRad | keys: description, value, quantity, default_unit, limits, visible_if, copy_for>,
 <Parameter: requiv_max=5.69794861284 solRad | keys: description, value, quantity, default_unit, limits, visible_if, copy_for>]



In [19]:

    
print(b.filter('mass', component='primary'))









    



ParameterSet: 2 parameters
*         mass@primary@component: 22.6428147622 solMass
         mass@primary@constraint: (39.478418 * ({sma@binary@component} ** 3.000000)) / ((({period@binary@component} ** 2.000000) * (1.000000 + {q@binary@component})) * 2942.206217504418873431859537959099)

Environment Variables

Some settings cannot be changed after importing PHOEBE, so they are available via environment variables. These can be set in a variety of ways:

Setting inline before calling python will set for that single session of PHOEBE:

PHOEBE_ENABLE_PLOTTING=FALSE python [script.py]

Setting via the os package in python before importing PHOEBE allows you to set the setting everytime you run a given script:

import os
os.environ['PHOEBE_ENABLE_PLOTTING'] = 'FALSE'
import phoebe

Note for all boolean settings, the string is converted to uppercase and compared to 'TRUE'.

PHOEBE_ENABLE_PLOTTING

PHOEBE_ENABLE_PLOTTING (TRUE by default) allows for disabling plotting within PHOEBE and therefore skipping the import of all plotting libraries (which take up a significant amount of the time it takes to import phoebe).

PHOEBE_ENABLE_ONLINE_PASSBANDS

PHOEBE_ENABLE_ONLINE_PASSBANDS (TRUE by default) dictates whether online passbands are queried and available for on-the-fly downloading. If you are sure you have all the local passbands you need, set this to False to save some time.