pint.polycos

Polynomial coefficients for phase prediction

Polycos designed to predict the pulsar’s phase and pulse-period over a given interval using polynomial expansions.

The pulse phase and frequency at time T are then calculated as:

\[ \begin{align}\begin{aligned}\Delta T = 1440(T-T_{\rm mid})\\\phi = \phi_0 + 60 \Delta T f_0 + COEFF[1] + COEFF[2] \Delta T + COEFF[3] \Delta T^2 + \ldots\\f({\rm Hz}) = f_0 + \frac{1}{60}\left( COEFF[2] + 2 COEFF[3] \Delta T + 3 COEFF[4] \Delta T^2 + \ldots \right)\end{aligned}\end{align} \]

Examples

Read in polycos, predict phases:

>>> from pint.polycos import Polycos
>>> p = Polycos.read(filename)
>>> p.eval_abs_phase(mjds)

Or, to generate polycos from a timing model:

>>> from pint.models import get_model
>>> from pint.polycos import Polycos
>>> model = get_model(filename)
>>> p = Polycos.generate_polycos(model, 50000, 50001, "AO", 144, 12, 1400)

References

http://tempo.sourceforge.net/ref_man_sections/tz-polyco.txt

Functions

tempo_polyco_table_reader(filename)

Read tempo style polyco file to an astropy table.

tempo_polyco_table_writer(polycoTable[, ...])

Write tempo style polyco file from an astropy table.

tqdm(*args, **kwargs)

Classes

PolycoEntry(tmid, mjdspan, rph_int, ...)

One Polyco entry.

Polycos([filename, format])

A class for polycos model.