R.Hirschfeld@cwi.nl writes:
Despite the ugliness of floating point arithmetic (lack of associativity, for example) and my general distaste for it, I would have to agree that 64-bit floats are higher precision than 32-bit fixed-points, since more than half the bits are mantissa.
However, accounting systems DO NOT use 32 bit fixed point arithmetic. One client of mine had around $10Billion under management. Do you think they were doing their accounting on a system that could only deal with fixed point numbers of 45Million or so? Hell, individual trades are larger. Floating point systems are built to do approximate math on a very wide range of number sizes. Accounting systems require exact math -- down to the cent. Floats aren't suitable. Anyone who needs to understand why should go off and read Knuth, Volume 2. {erru