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ring-sum tex2html_wrap_inline5387 ring tex2html_wrap_inline5575 tex2html_wrap_inline5389 tex2html_wrap_inline5387 ring tex2html_wrap_inline5581 tex2html_wrap_inline5389 tex2html_wrap_inline5387 result ring tex2html_wrap_inline5389

  Create a new ring with the variables from both tex2html_wrap_inline5575 and tex2html_wrap_inline5581 . The monomial order of the result is the product order, where each variable of tex2html_wrap_inline5575 is greater than each variable of tex2html_wrap_inline5581 . If either or both of tex2html_wrap_inline5575 and tex2html_wrap_inline5581 is a quotient ring, then the result will be one as well. For example, 

%  ; the ring R has variables a,b,c,d, and S has variables x,y,z.
%  ring-sum R S T

%  pring T
; ring T
; characteristic           : 31991
; number of variables      : 7
;  4 variables for block 0 : abcd
;  3 variables for block 1 : xyz
; weights for block 0      : 1 1 1 1 
; weights for block 1      : 1 1 1 
; monomial order           : 4 3 c 
; top degree of a monomial : 512 512

Caveat: no warning message is given if there is a variable of tex2html_wrap_inline5575 with the same name as a variable of tex2html_wrap_inline5581 . In this case, the new ring is created. The two variables will have the same name, but be internally different. This means that when inputting a matrix, the second variable cannot be named: each occurence of the name refers to the variable corresponding to the ring tex2html_wrap_inline5575 .


Sorin Popescu
Fri Feb 14 17:37:19 EST 1997