next | previous | forward | backward | up | top | index | toc | Macaulay2 web site
Macaulay2Doc :: random(Type)

random(Type) -- random element of a type

Synopsis

Description

Synopsis

  • Usage:
    random T
  • Inputs:
  • Outputs:
    • a random instance of the type T. If the Height option specifies a number h and T is ZZ and , then the integers returned are in the range 0 .. h-1; for QQ the numerator and denominator are in the range 1 .. h.
i1 : random RR

o1 = .320674588268059

o1 : RR (of precision 53)
i2 : random CC_100

o2 = .482265170853895705786563478205+.525262710458512152591995444123*ii

o2 : CC (of precision 100)
i3 : tally for i to 100 list random GF 11

o3 = Tally{-1 => 1}
           -1 => 1
           -1 => 1
           -1 => 1
           -1 => 1
           -1 => 1
           -1 => 1
           -1 => 1
           -1 => 1
           -2 => 1
           -2 => 1
           -2 => 1
           -2 => 1
           -2 => 1
           -2 => 1
           -2 => 1
           -3 => 1
           -3 => 1
           -3 => 1
           -3 => 1
           -3 => 1
           -3 => 1
           -3 => 1
           -3 => 1
           -3 => 1
           -3 => 1
           -3 => 1
           -4 => 1
           -4 => 1
           -4 => 1
           -4 => 1
           -4 => 1
           -4 => 1
           -4 => 1
           -4 => 1
           -4 => 1
           -4 => 1
           -4 => 1
           -5 => 1
           -5 => 1
           -5 => 1
           -5 => 1
           -5 => 1
           -5 => 1
           -5 => 1
           -5 => 1
           -5 => 1
           -5 => 1
           -5 => 1
           0 => 1
           0 => 1
           0 => 1
           0 => 1
           0 => 1
           0 => 1
           1 => 1
           1 => 1
           1 => 1
           1 => 1
           1 => 1
           1 => 1
           1 => 1
           1 => 1
           1 => 1
           2 => 1
           2 => 1
           2 => 1
           2 => 1
           2 => 1
           2 => 1
           2 => 1
           2 => 1
           2 => 1
           2 => 1
           2 => 1
           2 => 1
           3 => 1
           3 => 1
           3 => 1
           3 => 1
           3 => 1
           4 => 1
           4 => 1
           4 => 1
           4 => 1
           4 => 1
           4 => 1
           4 => 1
           4 => 1
           4 => 1
           4 => 1
           5 => 1
           5 => 1
           5 => 1
           5 => 1
           5 => 1
           5 => 1
           5 => 1
           5 => 1
           5 => 1
           5 => 1

o3 : Tally
i4 : random GF(2,40)

      39    37    35    30    29    28    25    24    23    22    18    13  
o4 = a   + a   + a   + a   + a   + a   + a   + a   + a   + a   + a   + a   +
     ------------------------------------------------------------------------
      9    8    7    6
     a  + a  + a  + a  + a

o4 : GF 1099511627776

Synopsis

  • Usage:
    random(d,R)
  • Inputs:
  • Outputs:
    • a random homogeneous element of the ring R of degree d
i5 : R = ZZ[x,y];
i6 : random(5,R)

       5     4      3 2     2 3       4     5
o6 = 9x  + 2x y + 7x y  + 2x y  + 8x*y  + 9y

o6 : R
i7 : R = GF(25,Variable=>a)[x,y];
i8 : VerticalList for i to 6 list random(3,R)

     {         3             2              2             3  }
o8 = {(2a - 1)x  + (- a - 1)x y + (a - 1)x*y  + (- a - 1)y   }
     {           3             2       2       3             }
     {(- 2a - 1)x  + (- a + 2)x y - x*y  - 2a*y              }
     {        3            2               2    3            }
     {(a - 1)x  + (2a - 2)x y + (2a + 2)x*y  + y             }
     {           3             2                2    3       }
     {(- 2a - 1)x  + (- a - 2)x y + (- a + 2)x*y  - y        }
     {           3                2    3                     }
     {(- 2a - 1)x  + (- 2a - 1)x*y  - y                      }
     {    3           2                 2       3            }
     {2a*x  + (a + 2)x y + (- 2a - 2)x*y  - 2a*y             }
     {           3           2               2              3}
     {(- 2a + 2)x  + (a + 2)x y + (2a + 2)x*y  + (- 2a - 1)y }

o8 : VerticalList
The length of d, if it's a list, should be the same as degreeLength R.

See also