Module musx.mxml.meter
A class representing standard musical meters.
Expand source code
"""
A class representing standard musical meters.
"""
from fractions import Fraction
class Meter:
"""
Returns a meter with integer attributes num and den set.
Parameters
----------
num : int
The numerator, an integer between 1 and 16 inclusive.
den : int
The denominator, a power of 2 between 1 and 32 inclusive.
staffnum : int
The staff number of the meter, 0 if meter applies to all staffs.
"""
def __init__(self, num, den, staffnum):
if not isinstance(num, int):
raise TypeError(f"Invalid meter numerator: {num}.")
if not 1 <= num <= 16:
raise ValueError(f"Invalid meter numerator: {num}.")
if not isinstance(den, int):
raise TypeError(f"Invalid meter denominator: {den}.")
if not (den in [1, 2, 4, 8, 16, 32]):
raise ValueError(f"Invalid meter denominator: {den}.")
if not isinstance(staffnum, int):
raise ValueError(f"Invalid staff number: {num}")
self.num = num
"""The numerator number of the meter."""
self.den = den
"""The denominator number of the meter."""
self.staffnum = staffnum
"""The staff number of the meter (0=All)."""
def __str__(self):
"""
Returns the print representation of the meter.
"""
staff = "all" if self.staffnum == 0 else self.staffnum
return f"<Meter: {self.num}/{self.den} staff={staff}>" # {hex(id(self))
def __repr__(self):
"""
Returns the external representation of the meter.
"""
return f'Meter({self.num}, {self.den} , {self.staffnum})'
# def string(self):
# """
# Returns the string name of the meter, e.g. '6/8'
# """
# return f'{self.num}/{self.den}'
def is_compound(self):
"""
Returns true if the meter is compound (numerator 6, 9, 12, or 15).
"""
return self.num in [6, 9, 12, 15]
def is_simple(self):
"""
Returns true if the meter is simple (numerator 1, 2, 3, or 4).
"""
return self.num in [1, 2, 3, 4]
def is_complex(self):
"""
Returns true if the meter is complex (numerator 5, 7, 8, 10, 11, 13, or 14).
"""
return self.num in [5, 7, 8, 10, 11, 13, 14]
def is_duple(self):
"""
Returns true if the meter is duple (numerator 2 or 6).
"""
return self.num in [2, 6]
def is_triple(self):
"""
Returns true if the meter is triple (numerator 3 or 9).
"""
return self.num in [3, 9]
def is_quadruple(self):
"""
Returns true if the meter is quadruple (numerator 4 or 12).
"""
return self.num in [4, 12]
def is_quintuple(self):
"""
Returns true if the meter is quintuple (numerator 5 or 15).
"""
return self.num in [5, 15]
def is_septuple(self):
"""
Returns true if the meter is a septuple (numerator 7).
"""
return self.num in [7]
def beat(self):
"""
Returns a Fraction representing the meter's beat duration. For
example, 4/4 returns a beat of 1/4, 6/8 meter returns the beat 3/8,
and 3/2 returns a beat of 1/2.
"""
if self.is_simple():
return Fraction(1, self.den)
elif self.is_compound():
return Fraction(1, self.den) * 3
else:
raise NotImplementedError('Ooops! Odd meter beats not implemented.')
def measure_dur(self):
"""
Returns a Fraction representing the meter's total measure duration, in
beats. For example, 4/4 returns a duration Fraction of 1/1, 6/8 meter
returns 3/4, and 3/2 returns a duration of 3/2. See: Fraction.
"""
return Fraction(1, self.den) * self.numClasses
class Meter (num, den, staffnum)-
Returns a meter with integer attributes num and den set.
Parameters
num:int- The numerator, an integer between 1 and 16 inclusive.
den:int- The denominator, a power of 2 between 1 and 32 inclusive.
staffnum:int- The staff number of the meter, 0 if meter applies to all staffs.
Expand source code
class Meter: """ Returns a meter with integer attributes num and den set. Parameters ---------- num : int The numerator, an integer between 1 and 16 inclusive. den : int The denominator, a power of 2 between 1 and 32 inclusive. staffnum : int The staff number of the meter, 0 if meter applies to all staffs. """ def __init__(self, num, den, staffnum): if not isinstance(num, int): raise TypeError(f"Invalid meter numerator: {num}.") if not 1 <= num <= 16: raise ValueError(f"Invalid meter numerator: {num}.") if not isinstance(den, int): raise TypeError(f"Invalid meter denominator: {den}.") if not (den in [1, 2, 4, 8, 16, 32]): raise ValueError(f"Invalid meter denominator: {den}.") if not isinstance(staffnum, int): raise ValueError(f"Invalid staff number: {num}") self.num = num """The numerator number of the meter.""" self.den = den """The denominator number of the meter.""" self.staffnum = staffnum """The staff number of the meter (0=All).""" def __str__(self): """ Returns the print representation of the meter. """ staff = "all" if self.staffnum == 0 else self.staffnum return f"<Meter: {self.num}/{self.den} staff={staff}>" # {hex(id(self)) def __repr__(self): """ Returns the external representation of the meter. """ return f'Meter({self.num}, {self.den} , {self.staffnum})' # def string(self): # """ # Returns the string name of the meter, e.g. '6/8' # """ # return f'{self.num}/{self.den}' def is_compound(self): """ Returns true if the meter is compound (numerator 6, 9, 12, or 15). """ return self.num in [6, 9, 12, 15] def is_simple(self): """ Returns true if the meter is simple (numerator 1, 2, 3, or 4). """ return self.num in [1, 2, 3, 4] def is_complex(self): """ Returns true if the meter is complex (numerator 5, 7, 8, 10, 11, 13, or 14). """ return self.num in [5, 7, 8, 10, 11, 13, 14] def is_duple(self): """ Returns true if the meter is duple (numerator 2 or 6). """ return self.num in [2, 6] def is_triple(self): """ Returns true if the meter is triple (numerator 3 or 9). """ return self.num in [3, 9] def is_quadruple(self): """ Returns true if the meter is quadruple (numerator 4 or 12). """ return self.num in [4, 12] def is_quintuple(self): """ Returns true if the meter is quintuple (numerator 5 or 15). """ return self.num in [5, 15] def is_septuple(self): """ Returns true if the meter is a septuple (numerator 7). """ return self.num in [7] def beat(self): """ Returns a Fraction representing the meter's beat duration. For example, 4/4 returns a beat of 1/4, 6/8 meter returns the beat 3/8, and 3/2 returns a beat of 1/2. """ if self.is_simple(): return Fraction(1, self.den) elif self.is_compound(): return Fraction(1, self.den) * 3 else: raise NotImplementedError('Ooops! Odd meter beats not implemented.') def measure_dur(self): """ Returns a Fraction representing the meter's total measure duration, in beats. For example, 4/4 returns a duration Fraction of 1/1, 6/8 meter returns 3/4, and 3/2 returns a duration of 3/2. See: Fraction. """ return Fraction(1, self.den) * self.numInstance variables
var den-
The denominator number of the meter.
var num-
The numerator number of the meter.
var staffnum-
The staff number of the meter (0=All).
Methods
def beat(self)-
Returns a Fraction representing the meter's beat duration. For example, 4/4 returns a beat of 1/4, 6/8 meter returns the beat 3/8, and 3/2 returns a beat of 1/2.
Expand source code
def beat(self): """ Returns a Fraction representing the meter's beat duration. For example, 4/4 returns a beat of 1/4, 6/8 meter returns the beat 3/8, and 3/2 returns a beat of 1/2. """ if self.is_simple(): return Fraction(1, self.den) elif self.is_compound(): return Fraction(1, self.den) * 3 else: raise NotImplementedError('Ooops! Odd meter beats not implemented.') def is_complex(self)-
Returns true if the meter is complex (numerator 5, 7, 8, 10, 11, 13, or 14).
Expand source code
def is_complex(self): """ Returns true if the meter is complex (numerator 5, 7, 8, 10, 11, 13, or 14). """ return self.num in [5, 7, 8, 10, 11, 13, 14] def is_compound(self)-
Returns true if the meter is compound (numerator 6, 9, 12, or 15).
Expand source code
def is_compound(self): """ Returns true if the meter is compound (numerator 6, 9, 12, or 15). """ return self.num in [6, 9, 12, 15] def is_duple(self)-
Returns true if the meter is duple (numerator 2 or 6).
Expand source code
def is_duple(self): """ Returns true if the meter is duple (numerator 2 or 6). """ return self.num in [2, 6] def is_quadruple(self)-
Returns true if the meter is quadruple (numerator 4 or 12).
Expand source code
def is_quadruple(self): """ Returns true if the meter is quadruple (numerator 4 or 12). """ return self.num in [4, 12] def is_quintuple(self)-
Returns true if the meter is quintuple (numerator 5 or 15).
Expand source code
def is_quintuple(self): """ Returns true if the meter is quintuple (numerator 5 or 15). """ return self.num in [5, 15] def is_septuple(self)-
Returns true if the meter is a septuple (numerator 7).
Expand source code
def is_septuple(self): """ Returns true if the meter is a septuple (numerator 7). """ return self.num in [7] def is_simple(self)-
Returns true if the meter is simple (numerator 1, 2, 3, or 4).
Expand source code
def is_simple(self): """ Returns true if the meter is simple (numerator 1, 2, 3, or 4). """ return self.num in [1, 2, 3, 4] def is_triple(self)-
Returns true if the meter is triple (numerator 3 or 9).
Expand source code
def is_triple(self): """ Returns true if the meter is triple (numerator 3 or 9). """ return self.num in [3, 9] def measure_dur(self)-
Returns a Fraction representing the meter's total measure duration, in beats. For example, 4/4 returns a duration Fraction of 1/1, 6/8 meter returns 3/4, and 3/2 returns a duration of 3/2. See: Fraction.
Expand source code
def measure_dur(self): """ Returns a Fraction representing the meter's total measure duration, in beats. For example, 4/4 returns a duration Fraction of 1/1, 6/8 meter returns 3/4, and 3/2 returns a duration of 3/2. See: Fraction. """ return Fraction(1, self.den) * self.num