The five digits of precision alludes to an ASFixed value. An ASF= ixed value is a hybrid of an Integer and a Real.

Where:

- An integer is a binary number with bits encoding values from 0 to 2^32 = (unsigned) or -2^30 to 2^30 (signed)
- A real / floating point splits the bits between representing significan= t figures and a mantissa for the exponent

An ASFixed value shifts the meaning of the bits of a signed 32 bit integ= er value from representing 2^30 down to 2^0, to representing values between= 2^15 (32,767) to 2^0.

This leaves 15 bits to represent values 2^0 to 2^-15. 2^-1 being 0.5 (1/= 2), 2^-2 being 0.25 (1/4), etc., allowing for smaller rational numbers in b= etween integers, but the precision won=E2=80=99t be smaller than 1/(2^15). = If you take the log of 2^15, you get approximately 4.515.

For any number in a PDF that gets converted from a string to an ASFixed =
value, APDFL will read the full string. Given identical numbers before the =
decimal point, changes in the first four significant digits will result in =
the number being mapped to a different ASFixed value. If you also assume th=
e first four significant digits are identical, then changes to the fifth di=
git **can** result in the =
number being mapped to a different ASFixed value, but that's not guaranteed=
. Anything beyond 5 digits won=E2=80=99t affect the number's representation=
as an ASFixed value.

The number is only guaranteed to be mapped to different ASFixed values f=
or the first four significant digits. This is because the full five digits =
for the value are not significant; rather, **almost** five dig=
its are significant.

This means that numbers which are identical out to four significant digi=
ts, but have different fifth digit values, **could** be mapped to the same ASFixed value.

For example, xx.xxxx4 and xx.= xxxx5 could potentially be mapped to the same ASFixed value.