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NumericalAlgebraicGeometry :: toAffineChart(ZZ,List)

toAffineChart(ZZ,List) -- coordinates of a point in the projective space in an affine chart

Synopsis

Description

i1 : toAffineChart(2,{1,2,3,4,5,6}) 

      1  2  4  5
o1 = {-, -, -, -, 2}
      3  3  3  3

o1 : List
i2 : toAffineChart(2,{1,2,0,4,5,6}) 

o2 = infinity

o2 : InfiniteNumber
i3 : CC[x,y];
i4 : s = track({x^2-y^2},{x*y},{{1,1}})

o4 = {{3.06183e-17, 1.0001}}

o4 : List
i5 : toAffineChart(0, coordinates s#0)

o5 = {3.26636e16}

o5 : List
i6 : toAffineChart(1, coordinates s#0)

o6 = {3.06152e-17}

o6 : List

Caveat

Returns infinity if the i-th coordinate of x is zero.

See also