"""Collection of methods for type input checking."""
import re
import math
try:
INFPOS = math.inf
INFNEG = -1 * math.inf
except AttributeError:
# python 2
INFPOS = float('inf')
INFNEG = float('-inf')
[docs]def valid_string(value, input_name=''):
"""Check that a string is valid as an identifier."""
try:
illegal_match = re.search(r'[^.A-Za-z0-9_-]', value)
except TypeError:
raise TypeError('Input {} must be a text string. Got {}: {}.'.format(
input_name, type(value), value))
assert illegal_match is None, 'Illegal character "{}" found in {}'.format(
illegal_match.group(0), input_name)
assert len(value) > 0, 'Input {} "{}" contains no characters.'.format(
input_name, value)
assert len(value) <= 100, 'Input {} "{}" must be less than 100 characters.'.format(
input_name, value)
return value
def _number_check(value, input_name):
"""Check if value is a number."""
try:
number = float(value)
except (ValueError, TypeError):
raise TypeError('Input {} must be a number. Got {}: {}.'.format(
input_name, type(value), value))
return number
[docs]def float_in_range(value, mi=INFNEG, ma=INFPOS, input_name=''):
"""Check a float value to be between minimum and maximum."""
number = _number_check(value, input_name)
assert mi <= number <= ma, 'Input number {} must be between {} and {}. ' \
'Got {}'.format(input_name, mi, ma, value)
return number
[docs]def float_in_range_excl(value, mi=INFNEG, ma=INFPOS, input_name=''):
"""Check a float value to be greater than minimum and less than maximum."""
number = _number_check(value, input_name)
assert mi < number < ma, 'Input number {} must be greater than {} ' \
'and less than {}. Got {}'.format(input_name, mi, ma, value)
return number
[docs]def float_in_range_excl_incl(value, mi=INFNEG, ma=INFPOS, input_name=''):
"""Check a float value to be greater than minimum and less than/equal to maximum."""
number = _number_check(value, input_name)
assert mi < number <= ma, 'Input number {} must be greater than {} and less than ' \
'or equal to {}. Got {}'.format(input_name, mi, ma, value)
return number
[docs]def float_in_range_incl_excl(value, mi=INFNEG, ma=INFPOS, input_name=''):
"""Check a float value to be greater than/equal to minimum and less than maximum."""
number = _number_check(value, input_name)
assert mi <= number < ma, 'Input number {} must be greater than or equal to {} ' \
'and less than {}. Got {}'.format(input_name, mi, ma, value)
return number
[docs]def int_in_range(value, mi=INFNEG, ma=INFPOS, input_name=''):
"""Check an integer value to be between minimum and maximum."""
try:
number = int(value)
except ValueError:
# try to convert to float and then digit if possible
try:
number = int(float(value))
except (ValueError, TypeError):
raise TypeError('Input {} must be an integer. Got {}: {}.'.format(
input_name, type(value), value))
except (ValueError, TypeError):
raise TypeError('Input {} must be an integer. Got {}: {}.'.format(
input_name, type(value), value))
assert mi <= number <= ma, 'Input integer {} must be between {} and {}. ' \
'Got {}.'.format(input_name, mi, ma, value)
return number
[docs]def float_positive(value, input_name=''):
"""Check a float value to be positive."""
return float_in_range_excl(value, 0, INFPOS, input_name)
[docs]def int_positive(value, input_name=''):
"""Check if an integer value is positive."""
return int_in_range(value, 0, INFPOS, input_name)
[docs]def tuple_with_length(value, length=3, item_type=float, input_name=''):
"""Try to create a tuple with a certain value."""
try:
value = tuple(item_type(v) for v in value)
except (ValueError, TypeError):
raise TypeError('Input {} must be a {}.'.format(
input_name, item_type))
assert len(value) == length, 'Input {} length must be {} not {}'.format(
input_name, length, len(value))
return value
[docs]def list_with_length(value, length=3, item_type=float, input_name=''):
"""Try to create a list with a certain value."""
try:
value = [item_type(v) for v in value]
except (ValueError, TypeError):
raise TypeError('Input {} must be a {}.'.format(
input_name, item_type))
assert len(value) == length, 'Input {} length must be {} not {}'.format(
input_name, length, len(value))
return value