I'll give it a shot: * foo ← {⍺ ⍶ ⍵}*
This defines foo as an operator that applies the function on its two arguments. I.e. in the following example: * 10 +foo 20* 30 The foo operator simply applies + to 10 and 20, returning 30. In other words, ⍶ is the function that goes to the left of the operator name. Similarly, ⍹ is the function that goes on the right of the operator name: * bar ← {(⍺ ⍶ 2) ⍹ (⍵ **⍶** 3) }* * 10 +bar- 20* ¯11 The call to bar results in the following formula being evaluated: (10+2)-(20+3). Regards, Elias On 18 May 2016 at 10:48, Christian Robert <christian.rob...@polymtl.ca> wrote: > Sorry, no explanations given. > > hook←{⍵⍶⍹⍵} > +hook÷2 > 2.5 > hook←{⍵⍶⍹⍵⊣⎕←⍵⊣⎕←⍶⊣⎕←⍹⊣⎕←⍵} > +hook÷2 > 2 > DOMAIN ERROR > hook[1] λ←⍵ ⍶ ⍹ ⍵⊣⎕←⍵⊣⎕←⍶⊣⎕←⍹⊣⎕←⍵ > ^^ > please explain the principle to a newbie. > > I really want a working examples. > > > Xtian. > > > > On 2016-05-17 22:30, Xiao-Yong Jin wrote: > >> They are for direct function (operator?) definitions. Try: >> >> hook←{⍵⍶⍹⍵} >> +hook÷2 >> 2.5 >> >> On May 17, 2016, at 8:24 PM, Christian Robert < >>> christian.rob...@polymtl.ca> wrote: >>> >>> hi, >>> >>> in the result of "]help" I can see: >>> >>> >>> λ { ... } result >>> ⍺ { ... } left value argument >>> ⍵ { ... } right value argument >>> χ { ... } axis argument >>> ⍶ { ... } left function argument >>> ⍹ { ... } right function argument >>> >>> >>> can someone explain to me the usage of ⍶ and ⍹ >>> with some examples ? >>> >>> I understant the first four, but not the last two. >>> >>> many thanks, >>> >>> Xtian. >>> >>> >> >>