Python works: >>> sum(x for x in xrange(1000000000 + 1)) 500000000500000000 Or: >>> sum(xrange(1000000000+1)) 500000000500000000 Python’s int auto promotes to a Python long which supports arbitrary precision. It will produce the correct answer on 32 or 64 bit platforms. This can be seen by raising 2 to a power far greater than the bit width … Read more
See the docs for num.toStringAsFixed(). String toStringAsFixed(int fractionDigits) Returns a decimal-point string-representation of this. Converts this to a double before computing the string representation. If the absolute value of this is greater or equal to 10^21 then this methods returns an exponential representation computed by this.toStringAsExponential(). Examples: 1000000000000000000000.toStringAsExponential(3); // 1.000e+21 Otherwise the result is the … Read more
In most programming languages, floating point numbers are represented a lot like scientific notation: with an exponent and a mantissa (also called the significand). A very simple number, say 9.2, is actually this fraction: 5179139571476070 * 2 -49 Where the exponent is -49 and the mantissa is 5179139571476070. The reason it is impossible to represent … Read more
How can I exactly construct a time stamp of actual time with milliseconds precision? I suspect you mean millisecond accuracy. DateTime has a lot of precision, but is fairly coarse in terms of accuracy. Generally speaking, you can’t. Usually the system clock (which is where DateTime.Now gets its data from) has a resolution of around … Read more
Numeric precision refers to the maximum number of digits that are present in the number. ie 1234567.89 has a precision of 9 Numeric scale refers to the maximum number of decimal places ie 123456.789 has a scale of 3 Thus the maximum allowed value for decimal(5,2) is 999.99
You can set the precision directly on std::cout and use the std::fixed format specifier. double d = 3.14159265358979; cout.precision(17); cout << “Pi: ” << fixed << d << endl; You can #include <limits> to get the maximum precision of a float or double. #include <limits> typedef std::numeric_limits< double > dbl; double d = 3.14159265358979; cout.precision(dbl::max_digits10); … Read more
float_num.toFixed(2); Note:toFixed() will round or pad with zeros if necessary to meet the specified length.
Huge difference. As the name implies, a double has 2x the precision of float[1]. In general a double has 15 decimal digits of precision, while float has 7. Here’s how the number of digits are calculated: double has 52 mantissa bits + 1 hidden bit: log(253)÷log(10) = 15.95 digits float has 23 mantissa bits + … Read more
For money, always decimal. It’s why it was created. If numbers must add up correctly or balance, use decimal. This includes any financial storage or calculations, scores, or other numbers that people might do by hand. If the exact value of numbers is not important, use double for speed. This includes graphics, physics or other … Read more
You are running into the old problem with floating point numbers that not all numbers can be represented exactly. The command line is just showing you the full floating point form from memory. With floating point representation, your rounded version is the same number. Since computers are binary, they store floating point numbers as an … Read more