Bells¶

The Bell class represents a single bell. An object of type Bell is essentially an integer, and bells are numbered starting with the treble as 0. Member functions are provided to convert between this numerical representation and a printable character. The class library can cope with up to 256 bells, though only bells numbered from 0 to 32 may be described by a printable character.

class ringing.Bell([spec])¶

Constructs a Bell.

Bells may be constructed in a variety of ways:

>>> from ringing import Bell
>>> Bell(10)  # from an integer bell number
Bell(10)
>>> Bell('E')  # from a printable character
Bell(10)
>>> Bell(Bell(10))  # from another bell
Bell(10)

Bells are immutable once created.

This library makes extensive use of Bell objects as function parameters. These may be passed in the same ways:

as a bell
as a character representing a bell
as an integer bell number

If a bell parameter can’t be read then a TypeError or ValueError exception will be raised as most appropriate.

Parameters:

spec (Bell or int or string) –

Specification for constructing the bell. This might be:

Nothing. Constructs an object representing the treble (bell 0).
Another bell. Constructs a copy.
An integer bell number. Constructs an object representing that bell.
A character (unicode or bytes) representing a bell.

__lt__(bell)¶

__le__(bell)¶

__eq__(bell)¶

__ne__(bell)¶

__gt__(bell)¶

__ge__(bell)¶

Compare a bell to another:

>>> from ringing import Bell
>>> Bell(4) == '5'
True

Parameters:: row – value to compare
Returns:: result
Return type:: boolean

MAX_BELLS¶

Maximum number of bells that may be represented using symbols. If the number of bells exceeds this value, the extra bells will be shown as “*” characters.

This attribute is available on the class as well as instances of it:

>>> from ringing import Bell
>>> Bell.MAX_BELLS
33
>>> Bell(32).to_char()
'Z'
>>> Bell(33).to_char()
'*'

Type:: integer

to_char()¶

Returns a character representing a bell:

>>> from ringing import Bell
>>> Bell(4).to_char()
'5'

Returns:: character
Return type:: string

static is_symbol(character)¶

Checks whether a character is a valid bell symbol:

>>> from ringing import Bell
>>> Bell.is_symbol('5')
True

Parameters:: character (string) – character to check
Returns:: result
Return type:: boolean

static set_symbols([symbols])¶

Sets the bell symbols that are to be used:

>>> from ringing import Bell, Row
>>> Bell.set_symbols('abcdef')
>>> Row(6)
Row('abcdef')
>>> Bell.MAX_BELLS
6

Note that bell symbols are set on a global level. Omit the symbol specification in order to reset to the default symbols:

>>> from ringing import Bell, Row
>>> Bell.set_symbols('abcdef')
>>> Row(6)
Row('abcdef')
>>> Bell.set_symbols()
>>> Row(6)
Row('123456')

Parameters:: symbols (string) – symbols to use