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DOT

DOT(VAR1,VAR2,IDIM)     Compute the inner product of two variables along given dimension.

Arguments: VAR1 Variable 1
  VAR2 Variable 2
  IDIM

Index 1, 2, .. or 6 along which to compute the dot product

Result Axes: X

 inherited from argument(s)

  Y inherited from argument(s)
  Z inherited from argument(s)
  T inherited from argument(s)
  E inherited from argument(s)
  F inherited from argument(s)

This function is a "direction-changing function", whose result grid is determined by the value of a specific direction argument. The variables in arguments 1 and 2 must have axes of the same length in the dot-product directions.

Examples: Sketching the function call,

! For 1-D variables in x, compute the inner product along the common x axis
! The result is a scalar
yes? let product = DOT(Ax, Bx, 1)
 
! For 2-D variables that share z and t axes, compute the inner product along the common z axis
! The result has a grid in xt
yes? let product = DOT(Axzt, Bzt, 3)