Source code for mangadap.util.misc

# Licensed under a 3-clause BSD style license - see LICENSE.rst
# -*- coding: utf-8 -*-
"""

A catch-all module with miscellaneous utility functions.

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.. include license and copyright
.. include:: ../include/copy.rst

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.. include common links, assuming primary doc root is up one directory
.. include:: ../include/links.rst
"""
import numpy
#import time
#from scipy import sparse

[docs]def line_coeff(p1, p2): r""" Given two points on a line return the slope and intercept calculated as .. math:: m &= \frac{y_1 - y_2}{x_1 - x_2} \\ b &= y_2 - m\ x_2 Args: p1 (array-like): A two-element :math:`(x_1,y_1)` array with one of the two points on the line. p2 (array-like): A two-element :math:`(x_2,y_2)` array with one of the two points on the line. Returns: float: The slope (:math:`m`) and intercept (:math:`b`) of the line, respectively. .. warning:: Performs **no** checks of the input. """ m = (p1[1] - p2[1])/(p1[0]-p2[0]) b = p2[1] - m*p2[0] return m, b
#def where_not(indx, size): # """ # Return a tuple with the indices of a vector that were *not* selected # by a call to `numpy.where`_. **The function currently only works # for 1D vectors.** # # Args: # indx (tuple): Tuple returned by a call to `numpy.where`_ for a # 1D vector. # size (int): Length of the original vector in the call to # `numpy.where`_. # # .. warning:: # Performs **no** checks of the input. # # """ # return (numpy.setdiff1d(numpy.arange(0,size), indx[0]),) #def inverse_with_zeros(v, absolute=True): # """ # Invert an array with zeros, and handle them by setting the inverse # to zero. # # Args: # v (array-like): Array to invert # absolute (bool): Forces that the absolute value must be larger # than 0. Otherwise, any non-positive value is also masked # with a zero. # # Returns: # numpy.ndarray: Inverse of the array when the vector has values # that are greater than 0, otherwise set to 0.0. # """ # if isinstance(v, numpy.ma.MaskedArray): # if not absolute: ## v.mask |= numpy.invert(v > 0) # v[numpy.invert(v > 0)] = numpy.ma.masked # return 1.0/v ## _v = numpy.asarray(v).astype(float) # _v = numpy.atleast_1d(v).astype(float) # indx = numpy.absolute(_v) > 0 if absolute else _v > 0 # _v[indx] = 1.0/_v[indx] # _v[numpy.invert(indx)] = 0.0 # return _v
[docs]def is_number(s): """ Check if the provided object is a number by trying to convert it to a floating-point object. Args: s (:obj:`object`): The object to convert Returns: :obj:`bool`: True if the object can be converted. """ try: float(s) except (ValueError, TypeError): return False else: return True