Paul asks:

> Can anyone enlighten me on what the following 'defined' function in BBXL is
>  doing?
>
>        DEF REAL FNL(SHORT INTEGER I1,I2)=I2+65536*(I1-(0 MIN SGN(I2)))
>
>  I know that it tries to handle two 16 bit integers as a 32 bit integer that
>  it assigns to a "Real" variable, but I' having difficulty with the "(0 MIN
>  SGN(I2))" part.

Having never used Business BASIC, I can obviously claim no expertise, but if
BBXL is like other languages, the SGN part would return either a -1, 0 or 1,
depending on the sign of the variable I2. That value would then perhaps be
compared to 0, with the MIN of two returned, either a 0 or -1.

All of that would make sense if a 16-bit two's complement number was
attempting to be returned, based on the presence of the 65536 (where -1 in
16-bit two's complement equals 65535 in a 16-bit "raw" logical number, and
where 0 equals 0 and +1 equals +1 in the same arithmetic). Only if I2 were
negative, do you have to subtract one from the result for any number greater
than 32767 in order to make it a properly formatted 16-bit two's complement
("integer") number.

Wirt Atmar

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