# This file is part of xrayutilities.
#
# xrayutilities is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, see <http://www.gnu.org/licenses/>.
#
# Copyright (c) 2010-2020, 2023 Dominik Kriegner <dominik.kriegner@gmail.com>
"""
xrayutilities utilities contains a conglomeration of useful functions
which do not fit into one of the other files
"""
import fractions
import math
import numpy
from . import config
from .utilities_noconf import (ABC, check_kwargs, en2lam, # noqa: F401
energies, energy, exchange_filepath,
exchange_path, is_valid_variable_name, lam2en,
makeNaturalName, wavelength)
[docs]
def import_matplotlib_pyplot(funcname='XU'):
"""
lazy import function of matplotlib.pyplot
Parameters
----------
funcname : str
identification string of the calling function
Returns
-------
flag : bool
the flag is True if the loading was successful and False otherwise.
pyplot
On success pyplot is the matplotlib.pyplot package.
"""
try:
from matplotlib import pyplot as plt
return True, plt
except ImportError:
if config.VERBOSITY >= config.INFO_LOW:
print(f"{funcname}: Warning: plot functionality not available")
return False, None
[docs]
def import_mayavi_mlab(funcname='XU'):
"""
lazy import function of mayavi.mlab
Parameters
----------
funcname : str
identification string of the calling function
Returns
-------
flag : bool
the flag is True if the loading was successful and False otherwise.
mlab
On success mlab is the mayavi.mlab package.
"""
try:
from mayavi import mlab
return True, mlab
except ImportError:
if config.VERBOSITY >= config.INFO_LOW:
print(f"{funcname}: Warning: plot functionality not available")
return False, None
[docs]
def maplog(inte, dynlow="config", dynhigh="config"):
"""
clips values smaller and larger as the given bounds and returns the log10
of the input array. The bounds are given as exponent with base 10 with
respect to the maximum in the input array. The function is implemented in
analogy to J. Stangl's matlab implementation.
Parameters
----------
inte : ndarray
numpy.array, values to be cut in range
dynlow : float, optional
10^(-dynlow) will be the minimum cut off
dynhigh : float, optional
10^(-dynhigh) will be the maximum cut off
Returns
-------
ndarray
numpy.array of the same shape as inte, where values smaller/larger than
10^(-dynlow, dynhigh) were replaced by 10^(-dynlow, dynhigh)
Examples
--------
>>> maplog(((0.1 , 1e5, 1e6), (10, 100, 1000)), 5, 2)
array([[1., 4., 4.],
[1., 2., 3.]])
"""
if dynlow == "config":
dynlow = config.DYNLOW
if dynhigh == "config":
dynhigh = config.DYNHIGH
inte = numpy.asarray(inte)
mask = numpy.logical_not(numpy.isnan(inte))
if inte[mask].max() <= 0.0:
raise ValueError("XU.maplog: only negativ or zero values given. "
"Log is not defined!")
ma = inte[mask].max() * 10 ** (-1*dynhigh) # upper bound
mi = inte[mask].max() * 10 ** (-1*dynlow) # lower bound
return numpy.log10(numpy.minimum(numpy.maximum(inte, mi), ma))
[docs]
def frac2str(fnumber, denominator_limit=25, fmt='%7.4f'):
"""
convert a float to a string attempting to represent it as a fraction
Parameters
----------
fnumber : float
floating point number to be represented as string
denominator_limit : int
maximal integer used as denominator. If f can't be expressed
(within xu.config.EPSILON) by a fraction with a denominator
up to this number a floating point string will be returned
fmt : str
format string used in case a floating point representation is needed
Returns
-------
str
"""
frac = fractions.Fraction(fnumber).limit_denominator(denominator_limit)
if math.isclose(float(frac), fnumber, abs_tol=config.EPSILON):
return str(frac)
return fmt % fnumber