Craig Ringer wrote:
Justin wrote:
No floating point is being used every variable is declared as numeric on the Postgresql side and in the C++ which is the UI side everything is double.
`double' in C++ refers to double precision floating point. `double' is subject to all the usual fun with rational decimals being irrational binary floats (and vice versa).
One of the reasons I chose Java for my current work is that it has a built-in decimal type (like `numeric') called BigDecimal . This makes working with exact quantities a lot easier as there's no conversion and rounding occurring each time data goes to/from the database.
Not according to MS specific if i'm reading it correctly
Microsoft Specific > The double type contains 64 bits: 1 for sign, 11 for the exponent, and 52 for the mantissa. Its range is +/–1.7E308 with at least 15 digits of precision
Are there any particular decimal/numeric libraries people here like to use with C++ ? Or do you just use double precision floats and a good deal of caution?
I'd expect that using double would be OK so long as the scale of your numeric values never approaches the floating point precision limit of the double type. I'm far from sure about that, though, and it'd be handy to hear from people who're doing it. Personally I like to stick to numeric/decimal types.
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Craig Ringer