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D.13.4.2 displayTropicalLifting

Procedure from library tropical.lib (see tropical_lib).

displaytropcallifting(troplift[,#]); troplift list, # list

troplift is the output of tropicalLifting; the optional parameter # can be the string 'subst'


- the procedure displays the output of the procedure tropicalLifting
- if the optional parameter 'subst' is given, then the lifting is substituted into the ideal and the result is displayed

LIB "tropical.lib";
==> Welcome to polymake version
==> Copyright (c) 1997-2015
==> Ewgenij Gawrilow, Michael Joswig (TU Darmstadt)
==> http://www.polymake.org
ring r=0,(t,x,y,z),dp;
ideal i=-y2t4+x2,yt3+xz+y;
intvec w=2,-4,0,4;
==> LP algorithm being used: "cddgmp".
==> Groebner basis Engine being used: "gfan".
==> 0
==> 0
==> 0
==> The procedure has created a list of lists. The jth entry of this list
==> contains a ring, an integer and an intvec.
==> In this ring lives an ideal representing the wanted lifting,
==> if the integer is N then in the parametrisation t has to be replaced by t\
==> and if the ith component of the intvec is w[i] then the ith component in \
==> should be multiplied by t^-w[i]/N in order to get the parametrisation.
==> Suppose your list has the name L, then you can access the 1st ring via:
==> def LIFTRing=L[1]; setring LIFTRing; LIFT;
==> The lifting of the point in the tropical variety lives in the ring
==> Q[[t^(1/2)]]
==> The lifting has the form:
==> x=(1)*t^(4/2)
==> y=(1)
==> z=(-1)*1/t^(4/2) + (-1)*t^(2/2)
==> Substituting the solution into the ideal gives:
==> i[1]=0
==> i[2]=0