MySql decimal types are a little bit more complicated than just left-of and right-of the decimal point. The first argument is precision, which is the number of total digits. The second argument is scale which is the maximum number of digits to the right of the decimal point. Thus, (4,2) can be anything from -99.99 … Read more
A decimal will always have some default value. If you need to have a nullable type decimal, you can use decimal?. Then you can do myDecimal.HasValue
Use MySQL DECIMAL type? Standard SQL requires that DECIMAL(5,2) be able to store any value with five digits and two decimals, so values that can be stored in the salary column range from -999.99 to 999.99
Use the floatformat template filter, for example {{ price_a|floatformat:2 }}
Integer.toBinaryString() is an in-built method and will do quite well.
138630.78380386264 is not exactly representable to double precision. The closest double precision number (as found here) is 138630.783803862635977566242218017578125, which agrees with your findings. You ask why the conversion to decimal does not contain more precision. The documentation for Convert.ToDecimal() has the answer: The Decimal value returned by this method contains a maximum of 15 significant … Read more
Python floats are neither arbitary precision nor of unlimited size. When k = 349, 16.**k is much too large – that’s almost 2^1400. Fortunately, the decimal library allows arbitrary precision and can handle the size: import decimal decimal.getcontext().prec = 100 def pi(): pi = decimal.Decimal(0) for k in range(350): pi += (decimal.Decimal(4)/(decimal.Decimal(8)*decimal.Decimal(k+1))…)