  Pulsar timing is a process of iteratively fitting pulse arrival times to
constrain the spindown, astrometric, and possibly binary parameters of a
pulsar, by enforcing integer numbers of pulsar rotations between the arrival
times. Phase connection is the process of unambiguously determining those
rotation numbers between the times of arrival (TOAs) while determining a pulsar
timing solution. Pulsar timing currently requires a manual process of
step-by-step phase connection performed by individuals. In an effort to
quantify and streamline this process, we created the Algorithmic Pulsar Timer,
APT, an algorithm which can accurately phase connect and time isolated pulsars.
Using the statistical F-test and knowledge of parameter uncertainties and
covariances, the algorithm decides what new data to include in a fit, when to
add additional timing parameters, and which model to attempt in subsequent
iterations. Using these tools, the algorithm can phase-connect timing data that
previously required substantial manual effort. We tested the algorithm on 100
simulated systems, with a 97% success rate. This algorithm is the first of its
kind in pulsar timing, and sets the foundation for automated fitting of binary
pulsar systems.
