I wrote a quick program to brute-force search for conflicts and found that this approach does not always work. The strings ABFN and AAHM have the same ASCII sum and product, but are not anagrams of one another. Their ASCII sum is 279 and ASCII product is 23,423,400. There are a lot more conflicts than … Read more
UPD: This is a compiler optimization issue, obviously. While MinGW used only one div instruction in loop body, both GCC on Linux and MSVC failed to reuse the quotient from previous iteration. I think the best we could do is explicitly define quo and rem and calculate them in the same basic instruction block, to … Read more
I have looked at this paper here which describes how to approximate the exponential function for double precision. After a little research on Wikipedia about single precision floating point representation I have worked out the equivalent algorithms. They only implemented the exp function, so I found an inverse function for the log and then simply … Read more
>>> import math >>> print math.sin.__doc__ sin(x) Return the sine of x (measured in radians). math.sin expects its argument to be in radians, not degrees, so: >>> import math >>> print math.sin(math.radians(68)) 0.927183854567
Yes rounding errors, and it is effectively NOT the same hardware. The 32 bit version is targeting a different set of instructions and register sizes.
Solving quadratic equations is not as simple as most people think. The standard formula for solving a x^2 + b x + c = 0 is delta = b^2 – 4 a c x1 = (-b + sqrt(delta)) / (2 a) (*) x2 = (-b – sqrt(delta)) / (2 a) but when 4 a c … Read more
This works in general: ceil(number*10)/10 So in Ruby it should be like: (number*10).ceil/10.0
You’ve exceeded the number of significant digits available (~15 to 16) in double-precision floating-point values. Once you do that, you can’t expect the least significant digit(s) of your result to actually be meaningful/precise. If you need arbitrarily precise arithmetic in Java, consider using BigInteger and BigDecimal.
If you want to do it with Delphi, you could look into how the JclExprEval unit works, part of the JEDI Code Library. I wrote it several years ago (it’s a little over-engineered); it parses functions and variables and can hand you back a method pointer which evaluates the expression quickly. Pass the variables in … Read more