""" Joblib is a set of tools to provide **lightweight pipelining in Python**. In particular, joblib offers: 1. transparent disk-caching of the output values and lazy re-evaluation (memoize pattern) 2. easy simple parallel computing 3. logging and tracing of the execution Joblib is optimized to be **fast** and **robust** in particular on large data and has specific optimizations for `numpy` arrays. It is **BSD-licensed**. ============================== ============================================ **User documentation**: http://pythonhosted.org/joblib **Download packages**: http://pypi.python.org/pypi/joblib#downloads **Source code**: http://github.com/joblib/joblib **Report issues**: http://github.com/joblib/joblib/issues ============================== ============================================ Vision -------- The vision is to provide tools to easily achieve better performance and reproducibility when working with long running jobs. * **Avoid computing twice the same thing**: code is rerun over an over, for instance when prototyping computational-heavy jobs (as in scientific development), but hand-crafted solution to alleviate this issue is error-prone and often leads to unreproducible results * **Persist to disk transparently**: persisting in an efficient way arbitrary objects containing large data is hard. Using joblib's caching mechanism avoids hand-written persistence and implicitly links the file on disk to the execution context of the original Python object. As a result, joblib's persistence is good for resuming an application status or computational job, eg after a crash. Joblib strives to address these problems while **leaving your code and your flow control as unmodified as possible** (no framework, no new paradigms). Main features ------------------ 1) **Transparent and fast disk-caching of output value:** a memoize or make-like functionality for Python functions that works well for arbitrary Python objects, including very large numpy arrays. Separate persistence and flow-execution logic from domain logic or algorithmic code by writing the operations as a set of steps with well-defined inputs and outputs: Python functions. Joblib can save their computation to disk and rerun it only if necessary:: >>> from sklearn.externals.joblib import Memory >>> mem = Memory(cachedir='/tmp/joblib') >>> import numpy as np >>> a = np.vander(np.arange(3)).astype(np.float) >>> square = mem.cache(np.square) >>> b = square(a) # doctest: +ELLIPSIS ________________________________________________________________________________ [Memory] Calling square... square(array([[ 0., 0., 1.], [ 1., 1., 1.], [ 4., 2., 1.]])) ___________________________________________________________square - 0...s, 0.0min >>> c = square(a) >>> # The above call did not trigger an evaluation 2) **Embarrassingly parallel helper:** to make it easy to write readable parallel code and debug it quickly:: >>> from sklearn.externals.joblib import Parallel, delayed >>> from math import sqrt >>> Parallel(n_jobs=1)(delayed(sqrt)(i**2) for i in range(10)) [0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0] 3) **Logging/tracing:** The different functionalities will progressively acquire better logging mechanism to help track what has been ran, and capture I/O easily. In addition, Joblib will provide a few I/O primitives, to easily define logging and display streams, and provide a way of compiling a report. We want to be able to quickly inspect what has been run. 4) **Fast compressed Persistence**: a replacement for pickle to work efficiently on Python objects containing large data ( *joblib.dump* & *joblib.load* ). .. >>> import shutil ; shutil.rmtree('/tmp/joblib/') """ # PEP0440 compatible formatted version, see: # https://www.python.org/dev/peps/pep-0440/ # # Generic release markers: # X.Y # X.Y.Z # For bugfix releases # # Admissible pre-release markers: # X.YaN # Alpha release # X.YbN # Beta release # X.YrcN # Release Candidate # X.Y # Final release # # Dev branch marker is: 'X.Y.dev' or 'X.Y.devN' where N is an integer. # 'X.Y.dev0' is the canonical version of 'X.Y.dev' # __version__ = '0.9.4' from .memory import Memory, MemorizedResult from .logger import PrintTime from .logger import Logger from .hashing import hash from .numpy_pickle import dump from .numpy_pickle import load from .parallel import Parallel from .parallel import delayed from .parallel import cpu_count