ExtElement ExtElement -- multiplication of Ext-algebra elements

Synopsis

• Operator: SPACE

• Usage:

  u=x y

• Inputs:
  • x, an instance of the type ExtElement, $x$ is of type $E$, where $E$ is of type ExtAlgebra
  • y, an instance of the type ExtElement, $y$ is of type $E$
• Outputs:
  • u, an instance of the type ExtElement, $u$ is of type $E$, the Ext-algebra product of $x$ and $y$

Description

i1 : L = lieAlgebra{a,b,c}/{a b,b c}

o1 = L

o1 : LieAlgebra

i2 : E = extAlgebra(3,L)

o2 = E

o2 : ExtAlgebra

i3 : (ext_1+2 ext_0) ext_2

o3 =  - ext_3

o3 : E

See also

• ExtAlgebra -- the class of all Ext-algebras
• sign -- get the sign of a homogeneous element
• weight -- get the weight of a homogeneous element