Dot .

Dot can be used as a dyadic operator with dyadic operands

Operator Dot means Inner Product

      1 2 3 +.× 4 5 6
32
      3 ∧.= 3 3 3 3
1
      mat
1 2
3 4
      mat +.× mat   ⍝ matrix product
 7 10
15 22

Used with Jot in place of the left operand Jot Dot means Outer Product 

      1 2 3 ∘.× 4 5 6 7
 4  5  6  7
 8 10 12 14
12 15 18 21

Note

Dot is also used as a decimal point and as a name separator in namespace reference syntax.

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