Ambi – streamlined – loses SEQ operator

Ambi is proving to be a great extensible RPN calculator. Applying the ‘zen’ of RPN to programming fun!

Enjoy the new release of Ambi.

This week I have discovered that the seq operator is not necessary.  Initially, I thought that seq would be necessary, however it turns out that the other lambda operators are sufficient.  So we now can write an interative approximator of cuberoot in this way …

function; root3;
    import dup $n = $guess =;
    $guess $prev = $n $prev sq / $prev + .5 * $guess =;
    $guess $prev - abs .000000001 >;
    $guess export ;
125 root3 .

Not a seq in sight!   And we may rewrite the function as a recursive function this way …

function; inner-root3;
  import $n = import $prev = $prev $n $prev sq / + .5 * $guess = $guess $prev - abs .000000001 >;
  $guess $n inner-root3 $guess =;
  $guess export;

function; root3;
  import dup inner-root3 export ;

100 root3 .

In addition the current release adds the ++ and increment and decrement operators.

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