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5.1.125 ringlist
Syntax:
ringlist ( ring_expression )
ringlist ( qring_expression )
Type:
- list
Purpose:
- decomposes a ring/qring into a list of 4 (or 6 in the non-commutative case,
see ringlist (plural)) components:
-
the field description in the following format:
- for Q, Z/p:
the characteristic, type int (0 or prime number)
- for real, complex:
a list of:
the characteristic, type int (always 0)
the precision, type list (2 integers: external, internal precision)
the name of the imaginary unit, type string
- for transcendental or algebraic extensions:
described as a ringlist (that is, as list L with 4 entries:
L[1] the characteristic, L[2] the names of the parameters, L[3] the monomial
ordering for the ring of parameters (default: lp), L[4] the minimal
polynomial (as ideal))
- for Z, Z/n, Z/n^m a list ["integer", [n, m]] with:
the base n is of type int or bigint (if not given n = 0, Z/0 = Z)
the exponent m is of type int (if not given m = 1)
-
the names of the variables (a list L of strings: L[i] is the name of the i-th
variable)
-
the monomial ordering (a list L of lists): each block L[i] consists of
-
the name of the ordering ( string )
-
parameters specifying the ordering and the size of the block ( intvec : typically the weights for the variables [default: 1] )
-
the quotient ideal.
From a list of such structure, a new ring may be defined by the command ring
( see the following example ).
Example:
See
qring;
ring.
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