HP 50g Binary Number Formatting

[John Keith]

A somewhat different approach:

Code:


\<< \->STR 3. OVER SIZE 1. - SUB    @ Clean up binary string
  0. SWAP                           @ Initialize counter
  WHILE DUP SIZE                    @ Any bits left?
  REPEAT DUP 1. 4. SUB " " + UNROT  @ First 4 bits plus space
    5. OVER SIZE SUB                @ Rest of string
    SWAP 1. + SWAP                  @ Increment counter
  END DROP \->LIST "" + \GSLIST     @ Concatenate substrings
  1. OVER SIZE 1. - SUB             @ Remove final space
\>>

Note that the string in line 4 is one space, and the string in line 7 is an empty string. The reason for the empty string in line 7 is that \GSLIST (Sigma-list) can't handle lists with less than two elements.