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1.1       misho       1: BCMATH FAQ: 
                      2: 
                      3: 1) Why BCMATH?
                      4: 
                      5: The math routines of GNU bc become more generally useful in a
                      6: library form.  By separating the BCMATH library from GNU bc,
                      7: GNU bc can be under the GPL and BCMATH can be under the LGPL.
                      8: 
                      9: 2) Why BCMATH when GMP exists?
                     10: 
                     11: GMP has "integers" (no digits after a decimal), "rational numbers"
                     12: (stored as 2 integers) and "floats".  None of these will correctly
                     13: represent a POSIX BC number.  Floats are the closest, but will not
                     14: behave correctly for many computations.  For example, BC numbers have
                     15: a "scale" that represent the number of digits to represent after the
                     16: decimal point.  The multiplying two of these numbers requires one to
                     17: calculate an exact number of digits after the decimal point regardless
                     18: of the number of digits in the integer part.  GMP floats have a
                     19: "fixed, but arbitrary" mantissa and so multiplying two floats will end
                     20: up dropping digits BC must calculate.
                     21: