Macaulay2 » Documentation
Packages » NAGtypes :: toAffineChart(ZZ,List)
next | previous | forward | backward | up | index | toc

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

- Function: toAffineChart
- Usage:
    `y = toAffineChart(i,x)`
- Inputs:
  - i, an integer, the number of the standard chart
  - x, a list, projective coordinates of a point
- Outputs:
  - y, a list, coordinates of x in the i-th affine chart

## 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

## Caveat

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

## See also

- areEqual -- determine if solutions are equal

## Ways to use this method:

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

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/NAGtypes/doc-NAGtypes.m2:341:0.