HP 50G: Long Reals Run Faster than Reals?

[Gerald H]

Below are two programmes to find the number of prime integers up to the input limit.

The programme using long reals requires less time than the one with reals.

Why?

Code:


::
  CK1&Dispatch
  BINT1
  ::
    DUP
    %LN
    DUPUNROT
    %/
    DUPUNROT
    OVER
    %IP
    %3
    %-
    COERCE
    ONE_DO
    INDEX@
    UNCOERCE
    %*
    OVER
    %/
    ROTOVER
    %+
    3UNROLL
    LOOP
    2DROP
  ;
;

::
  CK1&Dispatch
  BINT1
  ::
    %>%%
    DUP
    %%LN
    DUPUNROT
    %%/
    DUPUNROT
    OVER
    %%INT
    %%3
    %%-
    %%>%
    COERCE
    ONE_DO
    INDEX@
    UNCOERCE%%
    %%*
    OVER
    %%/
    ROTOVER
    %%+
    3UNROLL
    LOOP
    2DROP
    %%>%
  ;
;