I'm not sure what you are looking for, but here's what I did:
f=: 13 :',.S=: (_2 }. S) ,%/ _2 {. ,.S=: (_2 }. S),*/_2 {.,.S=: (_2
}.S),-/_2 {.,.S=: (_2 }.S),+/_2 {.,.S=:S,(-x){.,.S=:(_1 }. S),-_1
{.S=:,.(S=:''''),y'
2 f 1 2
0
divide times minus plus 2 dup chs 1 2 enter clear ''
0
Linda
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Kip Murray
Sent: Thursday, June 05, 2014 1:46 AM
To: [email protected]
Subject: [Jprogramming] rpn calculator
The following emulates a simple reverse Polish notation calculator which
operates on numbers at the bottom of a stack, replacing them by the result.
How would you do it? (Beware of line wrap.)
clear =: 3 : ',.STACK =: '''''
enter =: 4 : ',.STACK =: STACK , x' NB. x a list of numbers
chs =: 3 : ',.STACK =: (_1 }. STACK), - _1 {. STACK'
dup =: 4 : ',.STACK =: STACK , (- x) {. STACK' NB. x a non-negative
integer
plus =: 3 : ',.STACK =: ( _2 }. STACK), +/ _2 {. STACK'
minus =: 3 : ',.STACK =: ( _2 }. STACK), -/ _2 {. STACK'
times =: 3 : ',.STACK =: ( _2 }. STACK), */ _2 {. STACK'
divide =: 3 : ',.STACK =: ( _2 }. STACK), %/ _2 {. STACK'
clear''
1 2 enter ''
1
2
chs '' NB. Change sign of bottom number
1
_2
2 dup'' NB. Can use dup to keep a copy of numbers about to be combined
1
_2
1
_2
plus'' NB. 1 plus _2 is _1
1
_2
_1
--
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