dask.array.absolute — Dask documentation (original) (raw)

dask.array.absolute¶

dask.array.absolute(x, /, out=None, *, where=True, casting='same_kind', order='K', dtype=None, _subok=True_[, _signature_]) = <ufunc 'absolute'>¶

This docstring was copied from numpy.absolute.

Some inconsistencies with the Dask version may exist.

Calculate the absolute value element-wise.

np.abs is a shorthand for this function.

Parameters

xarray_like

Input array.

outndarray, None, or tuple of ndarray and None, optional

A location into which the result is stored. If provided, it must have a shape that the inputs broadcast to. If not provided or None, a freshly-allocated array is returned. A tuple (possible only as a keyword argument) must have length equal to the number of outputs.

wherearray_like, optional

This condition is broadcast over the input. At locations where the condition is True, the out array will be set to the ufunc result. Elsewhere, the out array will retain its original value. Note that if an uninitialized out array is created via the defaultout=None, locations within it where the condition is False will remain uninitialized.

**kwargs

For other keyword-only arguments, see theufunc docs.

Returns

absolutendarray

An ndarray containing the absolute value of each element in x. For complex input, a + ib, the absolute value is \(\sqrt{ a^2 + b^2 }\). This is a scalar if x is a scalar.

Examples

import numpy as np
x = np.array([-1.2, 1.2])
np.absolute(x)
array([ 1.2, 1.2]) np.absolute(1.2 + 1j)
1.5620499351813308

Plot the function over [-10, 10]:

import matplotlib.pyplot as plt

x = np.linspace(start=-10, stop=10, num=101)
plt.plot(x, np.absolute(x))
plt.show()

Plot the function over the complex plane:

xx = x + 1j * x[:, np.newaxis]
plt.imshow(np.abs(xx), extent=[-10, 10, -10, 10], cmap='gray')
plt.show()

The abs function can be used as a shorthand for np.absolute on ndarrays.

x = np.array([-1.2, 1.2])
abs(x)
array([1.2, 1.2])