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7.7.10.0. makeUsl
Procedure from library ncalg.lib (see ncalg_lib).
- Usage:
- makeUsl(n,[p]); n an integer, n>1; p an optional integer (field characteristic)
- Return:
- ring
- Purpose:
- set up the U(sl_n) in the variables ( x(i),y(i),h(i) | i=1..n+1) over the field of char p
- Note:
- activate this ring with the
setring command
This presentation of U(sl_n) is the standard one, i.e. positive resp. negative roots are denoted by x(i) resp. y(i) and the Cartan elements are denoted by h(i).
The variables are ordered as x(1),...x(n),y(1),...,y(n),h(1),...h(n).
Example:
See also:
makeQsl3;
makeQso3;
makeUg2;
makeUgl;
makeUsl2.
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