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[x] m`:n y Evoke Gerund Conjunction

Rank Infinity -- operates on x and y as a whole -- WHY IS THIS IMPORTANT?

If m is a gerund,  m`:n creates a verb based on m.

Operand n is an integer (0, 3 or 6) specifying what the verb should do

See below: More Information

   gerund =: +&2`''   NB. create a gerund
   gerund             NB. Display it.  (It is a deeply boxed noun)
|| ||+|+-+-+|||
|| || ||0|2||||
|| || |+-+-+|||
|| |+-+-----+||
   gerund `:6         NB. Turn the gerund into a verb
   (gerund `:6) 8     NB. The verb will actually run

Common Uses

1. To turn a gerund representing a single verb into the actual verb, as above.

More Information

1. n must have the value 0, 3, or 6.

2.  m`:0 y or:  x m`:0 y applies the verb described by each atom of m separately, and collects the results, using the shape of m as the frame, into an array which becomes the result of  m`:n .

The verbs are executed monadically or dyadically depending on the invocation of  m`:n

   ((+:`*:) `:0) i. 3
0 2 4
0 1 4
   $ (({. +:`*:) `:0) i. 3   NB. m here is an atom, so the result has no leading axis

3.  m`:3 y is equivalent to  m/ y .

Verb  m`:3 can not be used dyadically.

4.  m`:6 converts the individual atoms of m to verbs, and creates a verb train of the resulting verbs.

This verb train (which must define a verb) is the result of  m`:6 , and may be used monadically or dyadically.


1. m`: sometimes gives a domain error if m is boxed and is not a valid gerund.