trinary mathematical operator: [sigma summation of a using variable b over range c].

- pi'a
- n-ary mathematical operator: operands are vectors to be treated as matrix rows.
- re'a
- unary mathematical operator: matrix transpose/dual; A
^{T}. - ri'o
- trinary mathematical operator: [integral of a with respect to b over range c].
- sa'i
- n-ary mathematical operator: operands are vectors to be treated as matrix columns.
- sa'o
- trinary mathematical operator: [derivative of a with respect to b of degree c].
- si'i
- trinary mathematical operator: [sigma summation of a using variable b over range c].