# scalarProduct(RootSystem,Weight,Weight) -- the scalar product of two weights

## Synopsis

• Function: scalarProduct
• Usage:
scalarProduct(R,u,v)
• Inputs:
• R, an instance of the type RootSystem,
• u, an instance of the type Weight, the first weight
• v, an instance of the type Weight, the second weight
• Outputs:
• , the scalar product of u and v

## Description

 i1 : R=rootSystemA(2) o1 = RootSystem{...8...} o1 : RootSystem i2 : u=weight(R,{1,2}) o2 = | 1 | | 2 | o2 : Weight i3 : v=weight(R,{0,3}) o3 = | 0 | | 3 | o3 : Weight i4 : scalarProduct(R,u,v) 5 o4 = - 2 o4 : QQ