Singular Manual: sysBin

D.10.2.4 sysBin

Procedure from library decodegb.lib (see decodegb_lib).

Usage:

sysBin (v,Q,n,[odd]); v,n,odd are int, Q is list of int's

          - v a number if errors,
          - Q is a defining set of the code,
          - n the length,
          - odd is an additional parameter: if
           set to 1, then the defining set is enlarged by odd elements,
           which are 2^(some power)*(some element in the def.set) mod n

Return:

the ring with the resulting system called 'bin'

Theory:

Based on Q of the given cyclic code, the procedure constructs the corresponding ideal 'bin' with the use of the Waring function. With its help one can solve the decoding problem. For basics of the method Generalized Newton identities.

Example:

LIB "decodegb.lib";
// [31,16,7] quadratic residue code
list l=1,5,7,9,19,25;
// we do not need even synromes here
def A=sysBin(3,l,31);
setring A;
print(bin);
==> S(1)+sigma(1),
==> S(5)+sigma(1)^5+sigma(1)^3*sigma(2)+sigma(1)^2*sigma(3)+sigma(1)*sigma(2)\
   ^2+sigma(2)*sigma(3),
==> S(7)+sigma(1)^7+sigma(1)^5*sigma(2)+sigma(1)^4*sigma(3)+sigma(1)^2*sigma(\
   2)*sigma(3)+sigma(1)*sigma(2)^3+sigma(1)*sigma(3)^2+sigma(2)^2*sigma(3),
==> S(9)+sigma(1)^9+sigma(1)^7*sigma(2)+sigma(1)^6*sigma(3)+sigma(1)^5*sigma(\
   2)^2+sigma(1)^4*sigma(2)*sigma(3)+sigma(1)*sigma(2)^4+sigma(1)*sigma(2)*s\
   igma(3)^2+sigma(2)^3*sigma(3)+sigma(3)^3,
==> S(19)+sigma(1)^19+sigma(1)^17*sigma(2)+sigma(1)^16*sigma(3)+sigma(1)^14*s\
   igma(2)*sigma(3)+sigma(1)^13*sigma(2)^3+sigma(1)^13*sigma(3)^2+sigma(1)^1\
   2*sigma(2)^2*sigma(3)+sigma(1)^11*sigma(2)^4+sigma(1)^9*sigma(2)^5+sigma(\
   1)^8*sigma(2)^4*sigma(3)+sigma(1)^8*sigma(2)*sigma(3)^3+sigma(1)^3*sigma(\
   2)^8+sigma(1)^2*sigma(2)*sigma(3)^5+sigma(1)*sigma(2)^9+sigma(1)*sigma(2)\
   ^3*sigma(3)^4+sigma(1)*sigma(3)^6+sigma(2)^8*sigma(3)+sigma(2)^5*sigma(3)\
   ^3+sigma(2)^2*sigma(3)^5,
==> S(25)+sigma(1)^25+sigma(1)^23*sigma(2)+sigma(1)^22*sigma(3)+sigma(1)^21*s\
   igma(2)^2+sigma(1)^20*sigma(2)*sigma(3)+sigma(1)^17*sigma(2)^4+sigma(1)^1\
   7*sigma(2)*sigma(3)^2+sigma(1)^16*sigma(2)^3*sigma(3)+sigma(1)^16*sigma(3\
   )^3+sigma(1)^11*sigma(2)*sigma(3)^4+sigma(1)^10*sigma(3)^5+sigma(1)^9*sig\
   ma(2)^5*sigma(3)^2+sigma(1)^9*sigma(2)^2*sigma(3)^4+sigma(1)^8*sigma(2)^7\
   *sigma(3)+sigma(1)^8*sigma(2)^4*sigma(3)^3+sigma(1)^8*sigma(2)*sigma(3)^5\
   +sigma(1)^7*sigma(2)^9+sigma(1)^6*sigma(2)^8*sigma(3)+sigma(1)^5*sigma(2)\
   ^10+sigma(1)^4*sigma(2)^9*sigma(3)+sigma(1)*sigma(2)^12+sigma(1)*sigma(2)\
   ^9*sigma(3)^2+sigma(1)*sigma(3)^8+sigma(2)^11*sigma(3)+sigma(2)^8*sigma(3\
   )^3