SQLServer float and C#/VB double have the same representation. This is the correct mapping. What you don’t want to do is map SQL Server float to C#/VB float as that may involve a loss of precision. SQL Server real maps onto C#/VB float. T-SQL float and real type definitions can be found at MSDN. C# … Read more
Having tried a simple program (using both 0 and 100, to show the difference between “special” constants and general ones) the Sun Java 6 compiler will output the same bytecode for both 1 and 2 (cases 3 and 4 are identical to 2 as far as the compiler is concerned). So for example: double x … Read more
it takes the localization settings at runtime into account… perhaps you are running this on a system where . is not the decimal point but , instead… In your specific case I assume you want a fixed culture regardless of the system you are running on with . as the decimal point: double.TryParse(“0.0000”, NumberStyles.Number, CultureInfo.CreateSpecificCulture … Read more
Option 1 is closest: double d = rs.getDouble(1); if (rs.wasNull()) { // do something } else { // use d } It’s not very nice, but that’s JDBC. If the column was null, the double value is considered “bad”, so you should check using wasNull() every time you read a primitive that is nullable in … Read more
Note the comma in your string: “1,07”. DecimalFormat uses a locale-specific separator string, while Double.parseDouble() does not. As you happen to live in a country where the decimal separator is “,”, you can’t parse your number back. However, you can use the same DecimalFormat to parse it back: DecimalFormat df=new DecimalFormat(“0.00”); String formate = df.format(value); … Read more
OP wants leading zeroes. If that’s the case, then as per Tofubeer: DecimalFormat decim = new DecimalFormat(“0.00”); Edit: Remember, we’re talking about formatting numbers here, not the internal representation of the numbers. Double price = 32.0; DecimalFormat decim = new DecimalFormat(“0.00”); Double price2 = Double.parseDouble(decim.format(price)); System.out.println(price2); will print price2 using the default format. If you … Read more
You can set the culture of the current thread to any culture you want: Thread.CurrentThread.CurrentCulture = System.Globalization.CultureInfo.InvariantCulture; Note that changing the culture also affects things like string comparison and sorting, date formats and parsing of dates and numbers.
The reason for the difference is simple, if not obvious. If you use the equality operator ==, then you’re using the IEEE test for equality. If you’re using the Equals(object) method, then you have to maintain the contract of object.Equals(object). When you implement this method (and the corresponding GetHashCode method), you have to maintain that … Read more
It is all explained in the javadoc: Note that in most cases, for two instances of class Double, d1 and d2, the value of d1.equals(d2) is true if and only if d1.doubleValue() == d2.doubleValue() also has the value true. However, there are two exceptions: If d1 and d2 both represent Double.NaN, then the equals method … Read more
Number.MIN_VALUE is 5e-324, i.e. the smallest positive number that can be represented within float precision, i.e. that’s as close as you can get to zero. It defines the best resolution floats give you. Now the overall smallest value is Number.NEGATIVE_INFINITY although that’s not really numeric in the strict sense.