Ticket #5546: trac_5546-1-pynac_matrix_vector.patch

File trac_5546-1-pynac_matrix_vector.patch, 2.2 KB (added by burcin, 4 years ago)

allow forming matrices and vectors from pynac expressions

  • sage/symbolic/ring.pxd 

    # HG changeset patch
# User Burcin Erocal <burcin@erocal.org>
# Date 1237912294 -3600
# Node ID 99916902b1d1b0674315779687b6d23133bb899f
# Parent  cdc1edc584f69da3df11190919feedd0bf1e2265
Change base class of sage.symbolic.ring.NSymbolicRing to CommutativeRing and
add is_exact and is_field methods. This allows constructing matrices and
vectors with pynac expressions.

diff --git a/sage/symbolic/ring.pxd b/sage/symbolic/ring.pxd
    a b  
    11include "../libs/ginac/decl.pxi" 
    22 
    3 from sage.rings.ring cimport Ring 
     3from sage.rings.ring cimport CommutativeRing 
    44 
    5 cdef class NSymbolicRing(Ring) 
     5cdef class NSymbolicRing(CommutativeRing) 

  • sage/symbolic/ring.pyx 

    diff --git a/sage/symbolic/ring.pyx b/sage/symbolic/ring.pyx
    a b  
    77#                  http://www.gnu.org/licenses/ 
    88############################################################################### 
    99 
     10""" 
     11 
     12TESTS: 
     13    creating matrices and vectors with pynac expresssions:: 
     14    sage: var('x,y,z',ns=1) 
     15    (x, y, z) 
     16    sage: M = matrix(2,2,[x,y,z,x]) 
     17    sage: M.base_ring() 
     18    New Symbolic Ring 
     19 
     20    sage: v = vector([x,y]) 
     21    sage: v.base_ring() 
     22    New Symbolic Ring 
     23""" 
     24 
    1025include "../ext/stdsage.pxi" 
    1126include "../ext/cdefs.pxi" 
    1227 
    … …  
    2338 
    2439from sage.structure.element import RingElement 
    2540 
    26 cdef class NSymbolicRing(Ring): 
     41cdef class NSymbolicRing(CommutativeRing): 
    2742    """ 
    2843    Symbolic Ring, parent object for all symbolic expressions. 
    2944    """ 
    … …  
    138153            arctan(x^2) 
    139154        """ 
    140155        return new_Expression_from_GEx(g_wild(n)) 
    141      
     156 
     157    def is_field(self): 
     158        """ 
     159        Returns True, since symbolic expressions behave (mostly) like 
     160        field elements. 
     161 
     162        EXAMPLES: 
     163            sage: from sage.symbolic.ring import NSR 
     164            sage: NSR.is_field() 
     165            True 
     166        """ 
     167        return True 
     168 
     169    def is_exact(self): 
     170        """ 
     171        Returns False, since there are approximate symbolic expressions. 
     172 
     173        EXAMPLES: 
     174            sage: from sage.symbolic.ring import NSR 
     175            sage: NSR.is_exact() 
     176            False 
     177        """ 
     178        return False 
     179 
    142180 
    143181NSR = NSymbolicRing() 
    144182