JPhrases/VerbTrains

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2G. Verb Trains

The following phrases illustrate how trains may be substituted for other constructs, often giving expressions that are more readable, particularly to readers more familiar with expressions from mathematics:

m0=: >: @ +: @ i. First odd integers
m1=: 1: + 2: * i. Same as m0
m2=: +/ @ (1: + 2: * i.) Sum of odd integers
m3=: [: +/ 1: + 2: * i. Same as m2 using cap
m4=: m2 -: *: Sum of odds is square (Tautology)
m5=: < i. 1: The first element where x<y ;  also works for = ~: < <: >: > E.
m6=: < i. 0: The first element where not x<y
m7=: < i: 1: The last element where x<y
m8=: < i: 0: The last element where not x<y
m9=: [: +/ < The number of elements where x<y