pcset [-c] [-n|p|v] [inputfile ...]
By default, the output is the Fortean pitch-class set type (**pcset
).
Alternatively, the user may choose to output the corresponding
normal form
(**nf
) or the more succinct
prime form
(**pf
) or the associated
interval-class vector
(**iv
).
See
REFERENCES below.
In addition to accepting **semits
or **pc
inputs,
pcset
can also process **nf
, **iv
,
**pf
or **pcset
inputs.
This permits the user to determine the normal form, prime form or
interval-class vector for a given pc-set, or the interval-class vector for a given
pc-set, prime form, or normal form, etc.
For all of the above translations, pcset also provides a complementation operator, where output values corresponding to the pitch-class set complement. For example, when the complementation option is invoked, an input consisting of the pitch-classes (0,4,7,10) would produce an output pertinent to the complementary set (1,2,3,5,6,8,9,11). Complementation can be applied to any accepted input type, including normal form, prime form, interval-class vector, and pc-set. Note that if the input consists of all twelve pitch-classes, pcset produces a null token as the set complement.
When provided with **semits
or **pc
inputs,
pcset
treats each input record as a set of pitches.
Unisons and other pitch-class duplications have no effect on the output.
Rests within a set of pitches are ignored;
where an input record consists solely of one or more
rests, a null-token is output.
The
pcset
command is able to translate any of the representations listed below.
For descriptions of the various input representations
(including **pcset
) refer to Section 2
(Representation Reference)
of this reference manual.
It is recommended that output files produced using the pcset command should be given names with the distinguishing extensions `.pcs', `.nf' `.pf' or `.iv' -- depending on the selected option.
**iv
interval-class vector representation **nf
normal form for pitch-class sets **pc
pitch-class representation **pcset
Fortean pitch-class set name **pf
prime form representation **semits
equal-tempered semitones with respect to middle C=0 (e.g. 12 = C5)
Options are specified in the command line.
-c generate output for set complement -h displays a help screen summarizing the command syntax -n output normal form ( **nf
) spine-p output prime form ( **pf
) spine-v output interval-class vector ( **iv
) spine
By default, the
pcset
command outputs a **pcset
representation.
The
-n
option causes
pcset
to output normal form (**nf
) data instead of **pcset
data.
"Normal form" is a standard way of representing the interval
structure of any arbitrary set of pitch-classes.
The
-p
option causes
pcset
to output the prime form (**pf
) for the input.
Prime form is analogous to rearranging notes in a chord so that
the spelling is in root position,
close position, transposed so that the root of the chord is C.
By way of example, any major chord (having any root, in any inversion,
with any spelling) will have the normal form: 0,4,7 -- namely, a given
(basic) pitch, plus a pitch 4 semitones above than the basic pitch,
plus a pitch 7 semitones above the basic pitch.
(See REFERENCES.)
The
-v
option causes interval-class vector information (**iv
) to be output
rather than **pcset
data.
All pitch-class sets can be characterized according to the possible
interval-classes that can be constructed.
The six-element interval-class vector specifies the abundance
of various interval-classes from 1 semitone to 6 semitones.
(See REFERENCES.)
Note that the
iv
command, the
nf
command, and the
pf
command are aliases for
pcset -v
,
pcset -n
and
pcset -p
respectively.
webern
:
pcset -v webern > webern.iv
The following command outputs the Fortean set type for the complement
of the sonorities given in the input file berg
:
pcset -c berg > berg.pcs
The following command outputs the normal form representation
for sets formed from successive
sonorities in the input file boulez
:
pcset -n boulez.nf
John Rahn, Basic Atonal Theory. New York: Longman Inc., 1980.
Straus, J. Introduction to Post-Tonal Theory. Englewood Cliffs, N.J.: Prentice Hall, 1990.