Levi-Civita epsilon — e • ricci

Provides a labeled Levi-Civita epsilon (pseude) tensor. The indices are required to be lowered. Otherwise an error is thrown.

Usage

e(...)

Arguments

...: Index labels separated by commas optionally prefixed by "+" and "-" to indicate the index position (upper and lower respectively). If no prefix is provided, a lower index ("-") is assumed. This argument uses non-standard evaluation: any R symbol that is not a reserved keyword can be used.

Value

A labeled tensor object. The underlying data will differs depending on the number of labels provided.

See also

Underlying implementation: calculus::epsilon()

Wikipedia: Levi-Civita symbol

Other tensor symbols: d()

Examples

e(i, j)
#> <Labeled Array> [2x2] .(-i, -j)
#>      [,1] [,2]
#> [1,]    0    1
#> [2,]   -1    0

e(i, j, k)
#> <Labeled Array> [3x3x3] .(-i, -j, -k)