Package pygeodesy :: Module basics

Module basics

Some, basic definitions, functions and dependencies.

Use env variable PYGEODESY_XPACKAGES to avoid import of dependencies geographiclib, numpy and/or scipy. Set PYGEODESY_XPACKAGES to a comma-separated list of package names to be excluded from import.

Version: 24.04.28

Functions

str2ub(arg)
(INTERNAL) Helper, no-op.

ub2str(arg)
(INTERNAL) Helper, no-op.

clips(sb, limit=50, white='')
Clip a string to the given length limit.

copysign0(x, y)
Like math.copysign(x, y) except zero, unsigned.

copytype(x, y)
Return the value of x as type of y.

halfs2(str2)
Split a string in 2 halfs.

int1s(x)
Count the number of 1-bits in an int, unsigned.

isbool(obj)
Check whether an object is boolean.

isclass(obj)
Return True if obj is a class or type.

isCartesian(obj, ellipsoidal=None)
Is obj some Cartesian?

iscomplex(obj)
Check whether an object is a complex or complex str.

isDEPRECATED(obj)
Return True if obj is a DEPRECATED class, method or function, False if not or None if undetermined.

isfloat(obj)
Check whether an object is a float or float str.

isidentifier(obj)
Return True if obj is a Python identifier.

isinstanceof(obj, *classes)
Is ob an instance of one of the classes?

isint(obj, both=False)
Check for int type or an integer float value.

iskeyword(x, y)
y in x.

isLatLon(obj, ellipsoidal=None)
Is obj some LatLon?

islistuple(obj, minum=0)
Check for list or tuple type with a minumal length.

isNvector(obj, ellipsoidal=None)
Is obj some Nvector?

isodd(x)
Is x odd?

isscalar(obj)
Check for scalar types.

issequence(obj, *excls)
Check for sequence types.

isstr(obj)
Check for string types.

issubclassof(Sub, *Supers)
Check whether a class is a sub-class of some other class(es).

itemsorted(adict, *items_args, **asorted_reverse)
Return the items of adict sorted alphabetically, case-insensitively and in ascending order.

len2(items)
Make built-in function len work for generators, iterators, etc.

map1(fun1, *xs)
Apply a single-argument function to each xs and return a tuple of results.

map2(fun, *xs)
Apply a function to arguments and return a tuple of results.

neg(x, neg0=None)
Negate x and optionally, negate 0.0 and -0.0.

neg_(*xs)
Negate all xs with neg.

signBit(x)
Return signbit(x), like C++.

signOf(x)
Return sign of x as int.

splice(iterable, n=2, **fill)
Split an iterable into n slices.

unsigned0(x)
Unsign if 0.0.

Variables
	__all__ = `_ALL_LAZY.basics`

Function Details

clips (sb, limit=50, white='')

Clip a string to the given length limit.

Arguments:

sb - String (str or bytes).
limit - Length limit (int).
white - Optionally, replace all whitespace (str).

Returns:

The clipped or unclipped sb.

copysign0 (x, y)

Like math.copysign(x, y) except zero, unsigned.

Returns:: math.copysign(x, y) if x else type(x)(0).

copytype (x, y)

Return the value of x as type of y.

Returns:: type(y)(x).

halfs2 (str2)

Split a string in 2 halfs.

Arguments:

str2 - String to split (str).

Returns:

2-Tuple (_1st, _2nd) half (str).

Raises:

ValueError - Zero or odd len(str2).

Note: Both isint(True) and isint(False) return False (and no longer True).

isLatLon (obj, ellipsoidal=None)

Is obj some LatLon?

Arguments:

obj - The object (any type).
ellipsoidal - If None, return the type of any LatLon, if True, only an ellipsoidal LatLon type or if False, only a spherical LatLon type.

Returns:

type(obj if obj is a LatLon instance of the required type, False if a LatLon of an other type or {None} otherwise.

islistuple (obj, minum=0)

Check for list or tuple type with a minumal length.

Arguments:

obj - The object (any type).
minum - Minimal len required C({int}).

Returns:

True if obj is list or tuple with len at least minum, False otherwise.

isNvector (obj, ellipsoidal=None)

Is obj some Nvector?

Arguments:

obj - The object (any type).
ellipsoidal - If None, return the type of any Nvector, if True, only an ellipsoidal Nvector type or if False, only a spherical Nvector type.

Returns:

type(obj if obj is an Nvector instance of the required type, False if an Nvector of an other type or {None} otherwise.

isodd (x)

Is x odd?

Arguments:

x - Value (scalar).

Returns:

True if x is odd, False otherwise.

isscalar (obj)

Check for scalar types.

Arguments:

obj - The object (any type).

Returns:

True if obj is scalar, False otherwise.

issequence (obj, *excls)

Check for sequence types.

Arguments:

obj - The object (any type).
excls - Classes to exclude (type), all positional.

Returns:

True if obj is a sequence, False otherwise.

Note: Excluding tuple implies excluding namedtuple.

isstr (obj)

Check for string types.

Arguments:

obj - The object (any type).

Returns:

True if obj is str, False otherwise.

issubclassof (Sub, *Supers)

Check whether a class is a sub-class of some other class(es).

Arguments:

Sub - The sub-class (class).
Supers - One or more C(super) classes (class).

Returns:

True if Sub is a sub-class of any Supers, False if not (bool) or None if Sub is not a class or if no Supers are given or none of those are a class.

itemsorted (adict, *items_args, **asorted_reverse)

Return the items of adict sorted alphabetically, case-insensitively and in ascending order.

Arguments:

items_args - Optional positional argument(s) for method adict.items(B*{items_args}).
asorted_reverse - Use keyword argument asorted=False for alphabetical, case-sensitive sorting and reverse=True for sorting in descending order.

len2 (items)

Make built-in function len work for generators, iterators, etc. since those can only be started exactly once.

Arguments:

items - Generator, iterator, list, range, tuple, etc.

Returns:

2-Tuple (n, items) of the number of items (int) and the items (list or tuple).

map1 (fun1, *xs)

Apply a single-argument function to each xs and return a tuple of results.

Arguments:

fun1 - 1-Arg function (callable).
xs - Arguments (any positional).

Returns:

Function results (tuple).

map2 (fun, *xs)

Apply a function to arguments and return a tuple of results.

Unlike Python 2's built-in map, Python 3+ map returns a map object, an iterator-like object which generates the results only once. Converting the map object to a tuple maintains the Python 2 behavior.

Arguments:

fun - Function (callable).
xs - Arguments (list, tuple, ...).

Returns:

Function results (tuple).

neg (x, neg0=None)

Negate x and optionally, negate 0.0 and -0.0.

Arguments:

neg0 - Defines the return value for zero x: if None return 0.0, if True return NEG0 if x=0.0 and 0.0 if x=NEG0 or if False return x as-is (bool or None).

Returns:

-x if x else 0.0, NEG0 or x.

neg_ (*xs)

Negate all xs with neg.

Returns:: A map(neg, xs).

signBit (x)

Return signbit(x), like C++.

Returns:: True if x < 0 or NEG0 (bool).

signOf (x)

Return sign of x as int.

Returns:: -1, 0 or +1 (int).

splice (iterable, n=2, **fill)

Split an iterable into n slices.

Arguments:

iterable - Items to be spliced (list, tuple, ...).
n - Number of slices to generate (int).
fill - Optional fill value for missing items.

Returns:

A generator for each of n slices, iterable[i::n] for i=0..n.

Raises:

TypeError - Invalid n.

Note: Each generated slice is a tuple or a list, the latter only if the iterable is a list.

Example:

>>> from pygeodesy import splice

>>> a, b = splice(range(10))
>>> a, b
((0, 2, 4, 6, 8), (1, 3, 5, 7, 9))

>>> a, b, c = splice(range(10), n=3)
>>> a, b, c
((0, 3, 6, 9), (1, 4, 7), (2, 5, 8))

>>> a, b, c = splice(range(10), n=3, fill=-1)
>>> a, b, c
((0, 3, 6, 9), (1, 4, 7, -1), (2, 5, 8, -1))

>>> tuple(splice(list(range(9)), n=5))
([0, 5], [1, 6], [2, 7], [3, 8], [4])

>>> splice(range(9), n=1)
<generator object splice at 0x0...>

unsigned0 (x)

Unsign if 0.0.

Returns:: x if x else 0.0.