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r""" Operation Tables
This module implements general operation tables, which are very matrix-like. """
#***************************************************************************** # Copyright (C) 2010 Rob Beezer <beezer at ups.edu> # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 2 of the License, or # (at your option) any later version. # http://www.gnu.org/licenses/ #*****************************************************************************
r""" An object that represents a binary operation as a table.
Primarily this object is used to provide a :meth:`~sage.categories.magmas.Magmas.ParentMethods.multiplication_table` for objects in the category of magmas (monoids, groups, ...) and :meth:`~sage.categories.additive_magmas.AdditiveMagmas.ParentMethods.addition_table` for objects in the category of commutative additive magmas (additive monoids, groups, ...).
INPUT:
- ``S`` - a finite algebraic structure (or finite iterable)
- ``operation`` - a function of two variables that accepts pairs of elements from ``S``. A natural source of such functions is the Python :mod:`operator` module, and in particular :func:`operator.add` and :func:`operator.mul`. This may also be a function defined with ``lambda`` or ``def.``
- ``names`` - (default: ``'letters'``) The type of names used, values are:
* ``'letters'`` - lowercase ASCII letters are used for a base 26 representation of the elements' positions in the list given by :meth:`~sage.matrix.operation_table.OperationTable.column_keys`, padded to a common width with leading 'a's. * ``'digits'`` - base 10 representation of the elements' positions in the list given by :meth:`~sage.matrix.operation_table.OperationTable.column_keys`, padded to a common width with leading zeros. * ``'elements'`` - the string representations of the elements themselves. * a list - a list of strings, where the length of the list equals the number of elements.
- ``elements`` - (default: ``None``) A list of elements of ``S``, in forms that can be coerced into the structure, eg. their string representations. This may be used to impose an alternate ordering on the elements of `S``, perhaps when this is used in the context of a particular structure. The default is to use whatever ordering the ``S.list()`` method returns. `elements`` can also be a subset which is closed under the operation, useful perhaps when the set is infinite.
OUTPUT: An object with methods that abstracts multiplication tables, addition tables, Cayley tables, etc. It should be general enough to be useful for any finite algebraic structure whose elements can be combined with a binary operation. This is not necessarily meant be constructed directly, but instead should be useful for constructing operation tables of various algebraic structures that have binary operations.
EXAMPLES:
In its most basic use, the table needs a structure and an operation::
sage: from sage.matrix.operation_table import OperationTable sage: G=SymmetricGroup(3) sage: OperationTable(G, operation = operator.mul) * a b c d e f +------------ a| a b c d e f b| b a f e d c c| c e d a f b d| d f a c b e e| e c b f a d f| f d e b c a
With two operations present, we can specify which operation we want::
sage: from sage.matrix.operation_table import OperationTable sage: R=Integers(6) sage: OperationTable(R, operation=operator.add) + a b c d e f +------------ a| a b c d e f b| b c d e f a c| c d e f a b d| d e f a b c e| e f a b c d f| f a b c d e
The default symbol set for elements is lowercase ASCII letters, which take on a base 26 flavor for structures with more than 26 elements. ::
sage: from sage.matrix.operation_table import OperationTable sage: G=DihedralGroup(14) sage: OperationTable(G, operator.mul, names='letters') * aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az ba bb +------------------------------------------------------------------------------------ aa| aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az ba bb ab| ab aa ae ah ac aj ak ad am af ag ar ai ap at an av al aw ao az aq as ba bb au ax ay ac| ac ad af ai ab ag al aa an ae aj aq ah ao au am as ak ax ap ay ar av bb ba at aw az ad| ad ac ab aa af ae aj ai ah ag al ak an am ap ao ar aq av au at as ax aw az ay bb ba ae| ae ah aj am aa ak ar ab ap ac af av ad at az ai aw ag ba an bb al aq ay ax ao as au af| af ai ag an ad al aq ac ao ab ae as aa au ay ah ax aj bb am ba ak ar az aw ap av at ag| ag an al ao ai aq as af au ad ab ax ac ay ba aa bb ae az ah aw aj ak at av am ar ap ah| ah ae aa ab aj ac af am ad ak ar ag ap ai an at al av aq az ao aw ba as au bb ay ax ai| ai af ad ac ag ab ae an aa al aq aj ao ah am au ak as ar ay ap ax bb av at ba az aw aj| aj am ak ap ah ar av ae at aa ac aw ab az bb ad ba af ay ai ax ag al au as an aq ao ak| ak ap ar at am av aw aj az ah aa ba ae bb ax ab ay ac au ad as af ag ao aq ai al an al| al ao aq au an as ax ag ay ai ad bb af ba aw ac az ab at aa av ae aj ap ar ah ak am am| am aj ah ae ak aa ac ap ab ar av af at ad ai az ag aw al bb an ba ay aq ao ax au as an| an ag ai af al ad ab ao ac aq as ae au aa ah ay aj ax ak ba am bb az ar ap aw at av ao| ao al an ag aq ai ad au af as ax ab ay ac aa ba ae bb aj aw ah az at ak am av ap ar ap| ap ak am aj ar ah aa at ae av aw ac az ab ad bb af ba ag ax ai ay au al an as ao aq aq| aq au as ay ao ax bb al ba an ai az ag aw av af at ad ap ac ar ab ae am ak aa aj ah ar| ar at av az ap aw ba ak bb am ah ay aj ax as ae au aa ao ab aq ac af an al ad ag ai as| as ay ax ba au bb az aq aw ao an at al av ar ag ap ai am af ak ad ab ah aj ac ae aa at| at ar ap ak av am ah az aj aw ba aa bb ae ab ax ac ay af as ad au ao ag ai aq an al au| au aq ao al as an ai ay ag ax bb ad ba af ac aw ab az ae av aa at ap aj ah ar am ak av| av az aw bb at ba ay ar ax ap am au ak as aq aj ao ah an ae al aa ac ai ag ab af ad aw| aw bb ba ax az ay au av as at ap ao ar aq al ak an am ai aj ag ah aa ad af ae ac ab ax| ax ba bb aw ay az at as av au ao ap aq ar ak al am an ah ag aj ai ad aa ae af ab ac ay| ay as au aq ax ao an ba al bb az ai aw ag af av ad at ab ar ac ap am ae aa ak ah aj az| az av at ar aw ap am bb ak ba ay ah ax aj ae as aa au ac aq ab ao an af ad al ai ag ba| ba ax ay as bb au ao aw aq az at an av al ag ar ai ap ad ak af am ah ab ac aj aa ae bb| bb aw az av ba at ap ax ar ay au am as ak aj aq ah ao aa al ae an ai ac ab ag ad af
Another symbol set is base 10 digits, padded with leading zeros to make a common width. ::
sage: from sage.matrix.operation_table import OperationTable sage: G=AlternatingGroup(4) sage: OperationTable(G, operator.mul, names='digits') * 00 01 02 03 04 05 06 07 08 09 10 11 +------------------------------------ 00| 00 01 02 03 04 05 06 07 08 09 10 11 01| 01 05 03 07 06 00 08 02 04 10 11 09 02| 02 04 06 05 10 09 00 11 07 03 01 08 03| 03 06 08 00 11 10 01 09 02 07 05 04 04| 04 09 05 11 00 02 07 06 10 01 08 03 05| 05 00 07 02 08 01 04 03 06 11 09 10 06| 06 10 00 09 01 03 02 08 11 05 04 07 07| 07 08 04 01 09 11 05 10 03 02 00 06 08| 08 11 01 10 05 07 03 04 09 00 06 02 09| 09 02 11 06 07 04 10 05 00 08 03 01 10| 10 03 09 08 02 06 11 00 01 04 07 05 11| 11 07 10 04 03 08 09 01 05 06 02 00
If the group's elements are not too cumbersome, or the group is small, then the string representation of the elements can be used. ::
sage: from sage.matrix.operation_table import OperationTable sage: G=AlternatingGroup(3) sage: OperationTable(G, operator.mul, names='elements') * () (1,2,3) (1,3,2) +------------------------ ()| () (1,2,3) (1,3,2) (1,2,3)| (1,2,3) (1,3,2) () (1,3,2)| (1,3,2) () (1,2,3)
You can give the elements any names you like, but they need to be ordered in the same order as returned by the :meth:`~sage.matrix.operation_table.OperationTable.column_keys` method. ::
sage: from sage.matrix.operation_table import OperationTable sage: G=QuaternionGroup() sage: T=OperationTable(G, operator.mul) sage: T.column_keys() ((), (1,2,3,4)(5,6,7,8), ..., (1,7,3,5)(2,6,4,8)) sage: names=['1', 'I', 'J', '-1', '-K', 'K', '-I', '-J'] sage: T.change_names(names=names) sage: sorted(T.translation().items()) [('-1', (1,3)(2,4)(5,7)(6,8)),..., ('K', (1,8,3,6)(2,7,4,5))] sage: T * 1 I J -1 -K K -I -J +------------------------ 1| 1 I J -1 -K K -I -J I| I -1 K -I J -J 1 -K J| J -K -1 -J -I I K 1 -1| -1 -I -J 1 K -K I J -K| -K -J I K -1 1 J -I K| K J -I -K 1 -1 -J I -I| -I 1 -K I -J J -1 K -J| -J K 1 J I -I -K -1
With the right functions and a list comprehension, custom names can be easier. A multiplication table for hex digits (without carries)::
sage: from sage.matrix.operation_table import OperationTable sage: R=Integers(16) sage: names=[hex(Integer(a)) for a in R] sage: OperationTable(R, operation=operator.mul, names=names) * 0 1 2 3 4 5 6 7 8 9 a b c d e f +-------------------------------- 0| 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1| 0 1 2 3 4 5 6 7 8 9 a b c d e f 2| 0 2 4 6 8 a c e 0 2 4 6 8 a c e 3| 0 3 6 9 c f 2 5 8 b e 1 4 7 a d 4| 0 4 8 c 0 4 8 c 0 4 8 c 0 4 8 c 5| 0 5 a f 4 9 e 3 8 d 2 7 c 1 6 b 6| 0 6 c 2 8 e 4 a 0 6 c 2 8 e 4 a 7| 0 7 e 5 c 3 a 1 8 f 6 d 4 b 2 9 8| 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 9| 0 9 2 b 4 d 6 f 8 1 a 3 c 5 e 7 a| 0 a 4 e 8 2 c 6 0 a 4 e 8 2 c 6 b| 0 b 6 1 c 7 2 d 8 3 e 9 4 f a 5 c| 0 c 8 4 0 c 8 4 0 c 8 4 0 c 8 4 d| 0 d a 7 4 1 e b 8 5 2 f c 9 6 3 e| 0 e c a 8 6 4 2 0 e c a 8 6 4 2 f| 0 f e d c b a 9 8 7 6 5 4 3 2 1
This should be flexible enough to create a variety of such tables. ::
sage: from sage.matrix.operation_table import OperationTable sage: from operator import xor sage: T=OperationTable(ZZ, xor, elements=range(8)) sage: T . a b c d e f g h +---------------- a| a b c d e f g h b| b a d c f e h g c| c d a b g h e f d| d c b a h g f e e| e f g h a b c d f| f e h g b a d c g| g h e f c d a b h| h g f e d c b a sage: names=['000', '001','010','011','100','101','110','111'] sage: T.change_names(names) sage: T.set_print_symbols('^', '\\land') sage: T ^ 000 001 010 011 100 101 110 111 +-------------------------------- 000| 000 001 010 011 100 101 110 111 001| 001 000 011 010 101 100 111 110 010| 010 011 000 001 110 111 100 101 011| 011 010 001 000 111 110 101 100 100| 100 101 110 111 000 001 010 011 101| 101 100 111 110 001 000 011 010 110| 110 111 100 101 010 011 000 001 111| 111 110 101 100 011 010 001 000
sage: T = OperationTable([False, True], operator.or_, names = 'elements') sage: T . False True +------------ False| False True True| True True
TESTS:
Empty structures behave acceptably, though the ASCII table looks a bit odd. The LaTeX version works much better. ::
sage: from sage.matrix.operation_table import OperationTable sage: L=FiniteSemigroups().example(()) sage: L An example of a finite semigroup: the left regular band generated by () sage: T=OperationTable(L, operation=operator.mul) sage: T * + sage: T._latex_() '{\\setlength{\\arraycolsep}{2ex}\n\\begin{array}{r|*{0}{r}}\n\\multicolumn{1}{c|}{\\ast}\\\\\\hline\n\\end{array}}'
If the algebraic structure cannot be listed (like when it is infinite) then there is no way to create a table. ::
sage: from sage.matrix.operation_table import OperationTable sage: OperationTable(ZZ, operator.mul) Traceback (most recent call last): ... ValueError: Integer Ring is infinite
The value of ``elements`` must be a subset of the algebraic structure, in forms that can be coerced into the structure. Here we demonstrate the proper use first::
sage: from sage.matrix.operation_table import OperationTable sage: H=CyclicPermutationGroup(4) sage: H.list() [(), (1,2,3,4), (1,3)(2,4), (1,4,3,2)] sage: elts = ['()', '(1,3)(2,4)'] sage: OperationTable(H, operator.mul, elements=elts) * a b +---- a| a b b| b a
This can be rewritten so as to pass the actual elements of the group ``H``, using a simple ``for`` loop::
sage: L = H.list() #list of elements of the group H sage: elts = [L[i] for i in {0, 2}] sage: elts [(), (1,3)(2,4)] sage: OperationTable(H, operator.mul, elements=elts) * a b +---- a| a b b| b a
Here are a couple of improper uses ::
sage: elts.append(5) sage: OperationTable(H, operator.mul, elements=elts) Traceback (most recent call last): ... TypeError: unable to coerce 5 into Cyclic group of order 4 as a permutation group sage: elts[2]='(1,3,2,4)' sage: OperationTable(H, operator.mul, elements=elts) Traceback (most recent call last): ... TypeError: unable to coerce (1,3,2,4) into Cyclic group of order 4 as a permutation group sage: elts[2]='(1,2,3,4)' sage: OperationTable(H, operator.mul, elements=elts) Traceback (most recent call last): ... ValueError: (1,3)(2,4)*(1,2,3,4)=(1,4,3,2), and so the set is not closed
Unusable functions should be recognized as such::
sage: H=CyclicPermutationGroup(4) sage: OperationTable(H, operator.add) Traceback (most recent call last): ... TypeError: elements () and () of Cyclic group of order 4 as a permutation group are incompatible with operation: <built-in function add> sage: from operator import xor sage: OperationTable(H, xor) Traceback (most recent call last): ... TypeError: elements () and () of Cyclic group of order 4 as a permutation group are incompatible with operation: <built-in function xor>
.. TODO::
Provide color and grayscale graphical representations of tables. See commented-out stubs in source code.
AUTHOR:
- Rob Beezer (2010-03-15) """ r""" TESTS::
sage: from sage.matrix.operation_table import OperationTable sage: G=SymmetricGroup(3) sage: T=OperationTable(G, operator.mul) sage: TestSuite(T).run() """ # Determine the elements of S, specified or not # If elements are given, we check if they are all in S # Note: there exist listable infinite objects (like ZZ) except Exception: raise ValueError('unable to determine elements of %s' % S) else:
# Map elements to strings
# Determine the operation, if given by a string # Some simple symbols are supported, # Add support for other symbols in the supported dictionary # Triple is (function, ascii-symbol, latex-symbol) # ascii-symbol must be exactly one character wide # Note double-backslash to escape properly for latex add: (add, '+', '+'), mul: (mul, '*', '\\ast') } # default symbols for upper-left-hand-corner of table # We assume now that operation is a function that acts # as a closed binary operation on the elements. # If not, we'll discover that next in actual use.
# the elements might not be hashable. But if they are it is much # faster to lookup in a hash table rather than in a list! except TypeError: get_row = self._elts.index
r""" Helper function to create names of elements of algebraic structures.
INPUT: Identical to the input for :class:`OperationTable` and :meth:`change_names`, so look there for details.
OUTPUT:
- ``width`` - an integer giving the maximum width of the strings describing the elements. This is used for formatting the ASCII version of the table. - ``name_list`` - a list of strings naming the elements, in the same order as given by the :meth:`list` method. - ``name_dict`` - a dictionary giving the correspondence between the strings and the actual elements. So the keys are the strings and the values are the elements of the structure.
EXAMPLES:
This routine is tested extensively in the :class:`OperationTable` and :meth:`change_names` methods. So we just demonstrate the nature of the output here. ::
sage: from sage.matrix.operation_table import OperationTable sage: G=SymmetricGroup(3) sage: T=OperationTable(G, operator.mul) sage: w, l, d = T._name_maker('letters') sage: w 1 sage: l[0] 'a' sage: d['a'] ()
TESTS:
We test the error conditions here, rather than as part of the doctests for the :class:`OperationTable` and :meth:`change_names` methods that rely on this one. ::
sage: from sage.matrix.operation_table import OperationTable sage: G=AlternatingGroup(3) sage: T=OperationTable(G, operator.mul) sage: T._name_maker(['x']) Traceback (most recent call last): ... ValueError: list of element names must be the same size as the set, 1 != 3 sage: T._name_maker(['x', 'y', 4]) Traceback (most recent call last): ... ValueError: list of element names must only contain strings, not 4 sage: T._name_maker('blatzo') Traceback (most recent call last): ... ValueError: element names must be a list, or one of the keywords: 'letters', 'digits', 'elements' """ width = 1 else: else: else:
r""" Returns the element of the table, given the elements indexing its position.
INPUT: - pair -- two elements of the structure
OUTPUT: The element of the structure computed by the operation for the two input elements (in the order provided).
This uses the table as a look-up device. If you want to use the operation, then use the operation.
EXAMPLES::
sage: from sage.matrix.operation_table import OperationTable sage: G=DiCyclicGroup(3) sage: T=OperationTable(G, operator.mul) sage: T.column_keys() ((), (1,3,2,4)(5,7), ..., (1,2)(3,4)(5,7,6)) sage: T[G('(1,2)(3,4)(5,6,7)'), G('(1,3,2,4)(5,7)')] (1,4,2,3)(5,6)
TESTS::
sage: from sage.matrix.operation_table import OperationTable sage: G = DiCyclicGroup(3) sage: T = OperationTable(G, operator.mul) sage: T[G('(1,2)(3,4)(5,6,7)')] Traceback (most recent call last): ... TypeError: indexing into an operation table requires exactly two elements sage: T[G('(1,2)(3,4)(5,6,7)'), G('(1,3,2,4)(5,7)'), G('(1,3,2,4)(5,7)')] Traceback (most recent call last): ... TypeError: indexing into an operation table requires exactly two elements sage: T[2, 3] Traceback (most recent call last): ... IndexError: invalid indices of operation table: (2, 3) sage: T['(1,512)', '(1,3,2,4)(5,7)'] Traceback (most recent call last): ... IndexError: invalid indices of operation table: ((1,512), (1,3,2,4)(5,7)) """
r""" Returns the comparison between two tables.
INPUT:
- ``other`` - a second table to compare to ``self``.
OUTPUT: Tables are equal if they have the same operation and elements.
EXAMPLES::
sage: from sage.matrix.operation_table import OperationTable sage: G=CyclicPermutationGroup(6) sage: H=CyclicPermutationGroup(3) sage: P=OperationTable(G, operator.mul) sage: Q=OperationTable(G, operator.mul) sage: R=OperationTable(H, operator.mul) sage: S=OperationTable(G, operator.truediv) sage: P == P, P == Q, P == R, P == S (True, True, False, False) """
""" Inequality test, by negation of :meth:`.__eq__`.
EXAMPLES::
sage: from sage.matrix.operation_table import OperationTable sage: G=CyclicPermutationGroup(6) sage: H=CyclicPermutationGroup(3) sage: P=OperationTable(G, operator.mul) sage: Q=OperationTable(G, operator.mul) sage: R=OperationTable(H, operator.mul) sage: S=OperationTable(G, operator.truediv) sage: P != P, P != Q, P != R, P != S (False, False, True, True) """
r""" Returns a printable version of the operation table.
EXAMPLES::
sage: from sage.matrix.operation_table import OperationTable sage: R=Integers(5) sage: T=OperationTable(R, operation=operator.add) sage: print(T._repr_()) + a b c d e +---------- a| a b c d e b| b c d e a c| c d e a b d| d e a b c e| e a b c d """
r""" Set the symbols used for text and LaTeX printing of operation tables.
INPUT:
- ``ascii`` - a single character for text table - ``latex`` - a string to represent an operation in LaTeX math mode. Note the need for double-backslashes to escape properly.
EXAMPLES::
sage: from sage.matrix.operation_table import OperationTable sage: G=AlternatingGroup(3) sage: T=OperationTable(G, operator.mul) sage: T.set_print_symbols('@', '\\times') sage: T @ a b c +------ a| a b c b| b c a c| c a b sage: T._latex_() '{\\setlength{\\arraycolsep}{2ex}\n\\begin{array}{r|*{3}{r}}\n\\multicolumn{1}{c|}{\\times}&a&b&c\\\\\\hline\n{}a&a&b&c\\\\\n{}b&b&c&a\\\\\n{}c&c&a&b\\\\\n\\end{array}}'
TESTS::
sage: from sage.matrix.operation_table import OperationTable sage: G=AlternatingGroup(3) sage: T=OperationTable(G, operator.mul) sage: T.set_print_symbols('@', 5) Traceback (most recent call last): ... ValueError: LaTeX symbol must be a string, not 5 sage: T.set_print_symbols('@x@', '\\times') Traceback (most recent call last): ... ValueError: ASCII symbol should be a single character, not @x@ sage: T.set_print_symbols(5, '\\times') Traceback (most recent call last): ... ValueError: ASCII symbol should be a single character, not 5 """
r""" Returns a tuple of the elements used to build the table.
.. note:: ``column_keys`` and ``row_keys`` are identical. Both list the elements in the order used to label the table.
OUTPUT:
The elements of the algebraic structure used to build the table, as a list. But most importantly, elements are present in the list in the order which they appear in the table's column headings.
EXAMPLES::
sage: from sage.matrix.operation_table import OperationTable sage: G=AlternatingGroup(3) sage: T=OperationTable(G, operator.mul) sage: T.column_keys() ((), (1,2,3), (1,3,2)) """
# The ordered list of row and column elements are identical # given the current design, so these methods are aliases. If # expanded to allow different orderings (maybe interesting in # non-commutative cases?), then these will need to be # implemented separately.
r""" Returns a dictionary associating names with elements.
OUTPUT: A dictionary whose keys are strings used as names for entries of the table and values that are the actual elements of the algebraic structure.
EXAMPLES::
sage: from sage.matrix.operation_table import OperationTable sage: G=AlternatingGroup(3) sage: T=OperationTable(G, operator.mul, names=['p','q','r']) sage: sorted(T.translation().items()) [('p', ()), ('q', (1,2,3)), ('r', (1,3,2))] """
r""" Returns the table as a list of lists, using integers to reference the elements.
OUTPUT: The rows of the table, as a list of rows, each row being a list of integer entries. The integers correspond to the order of the elements in the headings of the table and the order of the output of the :meth:`list` method.
EXAMPLES::
sage: from sage.matrix.operation_table import OperationTable sage: C=CyclicPermutationGroup(3) sage: T=OperationTable(C, operator.mul) sage: T.table() [[0, 1, 2], [1, 2, 0], [2, 0, 1]] """
r""" For an existing operation table, change the names used for the elements.
INPUT:
- ``names`` - the type of names used, values are:
* ``'letters'`` - lowercase ASCII letters are used for a base 26 representation of the elements' positions in the list given by :meth:`list`, padded to a common width with leading 'a's. * ``'digits'`` - base 10 representation of the elements' positions in the list given by :meth:`list`, padded to a common width with leading zeros. * ``'elements'`` - the string representations of the elements themselves. * a list - a list of strings, where the length of the list equals the number of elements.
OUTPUT: ``None``. This method changes the table "in-place", so any printed version will change and the output of the :meth:`dict` will also change. So any items of interest about a particular table need to be copied/saved prior to calling this method.
EXAMPLES:
More examples can be found in the documentation for :class:`OperationTable` since creating a new operation table uses the same routine. ::
sage: from sage.matrix.operation_table import OperationTable sage: D=DihedralGroup(2) sage: T=OperationTable(D, operator.mul) sage: T * a b c d +-------- a| a b c d b| b a d c c| c d a b d| d c b a sage: T.translation()['c'] (1,2) sage: T.change_names('digits') sage: T * 0 1 2 3 +-------- 0| 0 1 2 3 1| 1 0 3 2 2| 2 3 0 1 3| 3 2 1 0 sage: T.translation()['2'] (1,2) sage: T.change_names('elements') sage: T * () (3,4) (1,2) (1,2)(3,4) +-------------------------------------------- ()| () (3,4) (1,2) (1,2)(3,4) (3,4)| (3,4) () (1,2)(3,4) (1,2) (1,2)| (1,2) (1,2)(3,4) () (3,4) (1,2)(3,4)| (1,2)(3,4) (1,2) (3,4) () sage: T.translation()['(1,2)'] (1,2) sage: T.change_names(['w', 'x', 'y', 'z']) sage: T * w x y z +-------- w| w x y z x| x w z y y| y z w x z| z y x w sage: T.translation()['y'] (1,2) """
r""" This method provides some backward compatibility for Cayley tables of groups, whose output was restricted to this single format.
EXAMPLES:
The output here is from the doctests for the old ``cayley_table()`` method for permutation groups. ::
sage: from sage.matrix.operation_table import OperationTable sage: G=PermutationGroup(['(1,2,3)', '(2,3)']) sage: T=OperationTable(G, operator.mul) sage: T.matrix_of_variables() [x0 x1 x2 x3 x4 x5] [x1 x0 x3 x2 x5 x4] [x2 x5 x4 x1 x0 x3] [x3 x4 x5 x0 x1 x2] [x4 x3 x0 x5 x2 x1] [x5 x2 x1 x4 x3 x0] sage: T.column_keys()[3]*T.column_keys()[3] == T.column_keys()[0] True """
#def color_table(): #r""" #Returns a graphic image as a square grid where entries are color coded. #""" #pass #return None
#def gray_table(): #r""" #Returns a graphic image as a square grid where entries are coded as grayscale values. #""" #pass #return None
r""" Returns a string that is an ASCII version of the table.
EXAMPLES::
sage: from sage.matrix.operation_table import OperationTable sage: R=Integers(5) sage: T=OperationTable(R, operator.add) sage: print(T._ascii_table()) + a b c d e +---------- a| a b c d e b| b c d e a c| c d e a b d| d e a b c e| e a b c d
The table should adjust its column width to accomodate the width of the strings used to represent elements. ::
sage: from sage.matrix.operation_table import OperationTable sage: R=Integers(10) sage: T=OperationTable(R, operator.mul, names='digits') sage: print(T._ascii_table()) * 0 1 2 3 4 5 6 7 8 9 +-------------------- 0| 0 0 0 0 0 0 0 0 0 0 1| 0 1 2 3 4 5 6 7 8 9 2| 0 2 4 6 8 0 2 4 6 8 3| 0 3 6 9 2 5 8 1 4 7 4| 0 4 8 2 6 0 4 8 2 6 5| 0 5 0 5 0 5 0 5 0 5 6| 0 6 2 8 4 0 6 2 8 4 7| 0 7 4 1 8 5 2 9 6 3 8| 0 8 6 4 2 0 8 6 4 2 9| 0 9 8 7 6 5 4 3 2 1
::
sage: from sage.matrix.operation_table import OperationTable sage: R=Integers(11) sage: T=OperationTable(R, operator.mul, names='digits') sage: print(T._ascii_table()) * 00 01 02 03 04 05 06 07 08 09 10 +--------------------------------- 00| 00 00 00 00 00 00 00 00 00 00 00 01| 00 01 02 03 04 05 06 07 08 09 10 02| 00 02 04 06 08 10 01 03 05 07 09 03| 00 03 06 09 01 04 07 10 02 05 08 04| 00 04 08 01 05 09 02 06 10 03 07 05| 00 05 10 04 09 03 08 02 07 01 06 06| 00 06 01 07 02 08 03 09 04 10 05 07| 00 07 03 10 06 02 09 05 01 08 04 08| 00 08 05 02 10 07 04 01 09 06 03 09| 00 09 07 05 03 01 10 08 06 04 02 10| 00 10 09 08 07 06 05 04 03 02 01
::
sage: from sage.matrix.operation_table import OperationTable sage: R=Integers(4) sage: T=OperationTable(R, operator.mul, names=['x','y','wwww', 'z']) sage: print(T._ascii_table()) * x y wwww z +-------------------- x| x x x x y| x y wwww z wwww| x wwww x wwww z| x z wwww y """
# Headers
# Row labels, body of table
r""" Returns a `LaTeX` version of the operation table as a string, using a `LaTeX` ``array`` environment.
EXAMPLES::
sage: from sage.matrix.operation_table import OperationTable sage: R=Integers(2) sage: T=OperationTable(R, operation=operator.mul) sage: T._latex_() '{\\setlength{\\arraycolsep}{2ex}\n\\begin{array}{r|*{2}{r}}\n\\multicolumn{1}{c|}{\\ast}&a&b\\\\\\hline\n{}a&a&a\\\\\n{}b&a&b\\\\\n\\end{array}}' """
# Headers
# Row label and body of table
# Finish |