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rank(DiffAlgDistribution) -- rank of the given distribution

Synopsis

Description

This routine returns the rank of the distribution L.


In this example we generate two random vector fields in three variables with polynomial coefficients of degree 2. Then we compute the rank of some distributions generated with them.

i1 : X = random newField(2,2,"a")

        2             2                            2            2          
o1 = (2x  - 2x x  + 6x  - 3x x  + 6x x )ax  + (- 7x  + 5x x  - x  - 2x x  -
        0     0 1     1     0 2     1 2   0        0     0 1    1     0 2  
     ------------------------------------------------------------------------
             2            2             2                     2
     x x  + x )ax  + (- 3x  - 4x x  + 7x  + 2x x  - 7x x  - 3x )ax
      1 2    2   1        0     0 1     1     0 2     1 2     2   2

o1 : DiffAlgField
i2 : Y = random newField(2,2,"a")

       2             2                    2           2     2               
o2 = (x  + 7x x  + 3x  + 2x x  + x x  + 8x )ax  + (- x  - 4x  - 7x x  - x x 
       0     0 1     1     0 2    1 2     2   0       0     1     0 2    1 2
     ------------------------------------------------------------------------
        2          2             2            2
     - x )ax  + (3x  - 4x x  + 7x  - 5x x  + x )ax
        2   1      0     0 1     1     0 2    2   2

o2 : DiffAlgField
i3 : rank dist {X,Y}

o3 = 2
i4 : rank dist {X,Y,X+Y,X-Y}

o4 = 2
i5 : rank dist {X,Y,X|Y}

o5 = 3

See also

Ways to use this method: