multihist

https://travis-ci.org/JelleAalbers/multihist.svg?branch=master

https://github.com/JelleAalbers/multihist

Thin wrapper around numpy's histogram and histogramdd.

Numpy has great histogram functions, which return (histogram, bin_edges) tuples. This package wraps these in a class with methods for adding new data to existing histograms, take averages, projecting, etc.

For 1-dimensional histograms you can access cumulative and density information, as well as basic statistics (mean and std). For d-dimensional histograms you can name the axes, and refer to them by their names when projecting / summing / averaging.

NB: The Scikit-HEP project (especially Henry Schreiner and Hans Dembinski) created a very cool library called boost-histogram. This is faster, more fully featured, and much more robust than multihist. It also has a numpy compatibility layer at boost_histogram.numpy. If you are starting a new project, I would recommend looking into boost-histogram rather than multihist.

Synopsis:

# Create histograms just like from numpy...
m = Hist1d([0, 3, 1, 6, 2, 9], bins=3)

# ...or add data incrementally:
m = Hist1d(bins=100, range=(-3, 4))
m.add(np.random.normal(0, 0.5, 10**4))
m.add(np.random.normal(2, 0.2, 10**3))

# Get the data back out:
print(m.histogram, m.bin_edges)

# Access derived quantities like bin_centers, normalized_histogram, density, cumulative_density, mean, std
plt.plot(m.bin_centers, m.normalized_histogram, label="Normalized histogram", linestyle='steps')
plt.plot(m.bin_centers, m.density, label="Empirical PDF", linestyle='steps')
plt.plot(m.bin_centers, m.cumulative_density, label="Empirical CDF", linestyle='steps')
plt.title("Estimated mean %0.2f, estimated std %0.2f" % (m.mean, m.std))
plt.legend(loc='best')
plt.show()

# Slicing and arithmetic behave just like ordinary ndarrays
print("The fourth bin has %d entries" % m[3])
m[1:4] += 4 + 2 * m[-27:-24]
print("Now it has %d entries" % m[3])

# Of course I couldn't resist adding a canned plotting function:
m.plot()
plt.show()

# Create and show a 2d histogram. Axis names are optional.
m2 = Histdd(bins=100, range=[[-5, 3], [-3, 5]], axis_names=['x', 'y'])
m2.add(np.random.normal(1, 1, 10**6), np.random.normal(1, 1, 10**6))
m2.add(np.random.normal(-2, 1, 10**6), np.random.normal(2, 1, 10**6))
m2.plot()
plt.show()

# x and y projections return Hist1d objects
m2.projection('x').plot(label='x projection')
m2.projection(1).plot(label='y projection')
plt.legend()
plt.show()

File	Mode	Size
tests
.bumpversion.cfg	-rw-r--r--	94 bytes
.gitignore	-rw-r--r--	746 bytes
.travis.yml	-rw-r--r--	949 bytes
HISTORY.rst	-rw-r--r--	2.4 KB
LICENSE	-rw-r--r--	1.1 KB
MANIFEST.in	-rw-r--r--	167 bytes
Multihist example.ipynb	-rw-r--r--	117.4 KB
README.rst	-rw-r--r--	2.7 KB
multihist.py	-rw-r--r--	35.3 KB
requirements.txt	-rw-r--r--	6 bytes
setup.py	-rw-r--r--	1.0 KB

README.rst