As of C++11, special cases were added to the suite of power functions (and others). C++11 [c.math] /11 states, after listing all the float/double/long double overloads (my emphasis, and paraphrased): Moreover, there shall be additional overloads sufficient to ensure that, if any argument corresponding to a double parameter has type double or an integer type, … Read more
The solution for arguments under 1.7976931348623157E308 (Double.MAX_VALUE) but supporting results with MILLIONS of digits: Since double supports numbers up to MAX_VALUE (for example, 100! in double looks like this: 9.332621544394415E157), there is no problem to use BigDecimal.doubleValue(). But you shouldn’t just do Math.pow(double, double) because if the result is bigger than MAX_VALUE you will just … Read more
pow() returns numbers as floating point. What is really returning is 24.99997 or something similar. But then you truncate it by assigning it to an integer and it comes out as 24. It’s ok to assignit to an integer in this case because you know then answer will always be an integer so you need … Read more
You have set a to be an int. pow() generates a floating point number, that in SOME cases may be just a hair less than 100 or 10000 (as we see here.) Then you stuff that into the integer, which TRUNCATES to an integer. So you lose that fractional part. Oops. If you really needed … Read more
MethodImplOptions.InternalCall That means that the method is actually implemented in the CLR, written in C++. The just-in-time compiler consults a table with internally implemented methods and compiles the call to the C++ function directly. Having a look at the code requires the source code for the CLR. You can get that from the SSCLI20 distribution. … Read more
From Here Looking at the pow() function: double pow (double base, double exponent); we know the parameters and return value are all double type. But the variable num, i and res are all int type in code above, when tranforming int to double or double to int, it may cause precision loss. For example (maybe … Read more