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MultiprojectiveVarieties :: projections

projections -- projections of a multi-projective variety

Synopsis

Description

i1 : X = projectiveVariety(ZZ/101[x_0..x_3]) ** projectiveVariety(ZZ/101[y_0..y_2]);

o1 : ProjectiveVariety, PP^3 x PP^2
i2 : projections X

o2 = {-- rational map --                                       ,
                    ZZ                          ZZ              
      source: Proj(---[x , x , x , x ]) x Proj(---[y , y , y ]) 
                   101  0   1   2   3          101  0   1   2   
                    ZZ                                          
      target: Proj(---[x , x , x , x ])                         
                   101  0   1   2   3                           
      defining forms: {                                         
                       x ,                                      
                        0                                       
                                                                
                       x ,                                      
                        1                                       
                                                                
                       x ,                                      
                        2                                       
                                                                
                       x
                        3
                      }
     ------------------------------------------------------------------------
     -- rational map --                                       }
                   ZZ                          ZZ
     source: Proj(---[x , x , x , x ]) x Proj(---[y , y , y ])
                  101  0   1   2   3          101  0   1   2
                   ZZ
     target: Proj(---[y , y , y ])
                  101  0   1   2
     defining forms: {
                      y ,
                       0
                      
                      y ,
                       1
                      
                      y
                       2
                     }

o2 : List

Ways to use projections :

For the programmer

The object projections is a method function.