(The above command lines assume that you are invoking spigot from a POSIX shell, so that expressions containing parentheses need to be single-quoted in order for spigot to receive them unmodified without the shell interfering. (Some will be much slower than others.) You could try some of these, for example: Spigot can also evaluate more complicated mathematical expressions. But in principle, given unlimited time and memory, it could just keep on going. by pressing Ctrl-C).Īs spigot generates more digits, it will slow gradually down and consume more and more memory to keep track of where it's got to, and one of time and memory will ultimately be the limit to how much data it can generate. In this default mode, spigot generates unbounded output: it will continue writing digits of π to the terminal until you interrupt it (e.g. The simplest thing spigot can do is to compute well-known mathematical constants such as π. it writes output as it goes along, and once it has read enough digits of an input number to know some of the output, it will print it. In the latter mode, it operates ‘on-line’, i.e. Spigot can evaluate expressions starting from numbers it can construct internally (integers, rationals, π, etc), and it can also read a number from a file or a pipe. So spigot can be useful if you really do need a lot of digits, or if you're doing a computation prone to numerical error, or as a cross-check on other calculating systems, but it wouldn't be usable outside that kind of specialist niche.) And because it evaluates a complicated expression as a whole, it's especially unsuited to any iterative algorithm which involves looking at the first result you get and then deciding what further arithmetic to do on it: normal arithmetic systems can do the next step of the algorithm with only the cost of the extra operations, but spigot would have to re-evaluate the entire thing from the start every time. You wouldn't want to use even its individual arithmetic operations and functions for any kind of bulk computation. (The downside of doing this is that spigot is slow, compared to the more usual methods of computer arithmetic. Spigot, on the other hand, does not output any digit until it is sure that digit is correct, so if you ask for (say) 100 digits of sin(sqrt(pi)) then you can be sure they are the right 100 digits. In particular, if you ask for a complex expression such as sin(sqrt(pi)), then most calculating systems would compute first pi, then sqrt(pi) and finally sin(sqrt(pi)), accumulating a rounding error at each step, so that the final result had a build-up of error and you would have to do some additional error analysis to decide how much of the output you could trust. This means that it does not suffer from rounding errors in principle, it can keep generating more and more digits of the number you asked for until it runs out of memory.
Spigot differs from the average calculating program in that it is an exact real calculator. It supports the usual arithmetic operations, square and cube roots, trigonometric and exponential functions, and a few other special functions such as erf.
DEGREE MODE IN MAGIC CALCULATOR MANUAL
This manual documents spigot, a command-line exact real calculator. Appendix B: Copyright statement and licence.Chapter 6: Output and return values of spigot.5.2 Exactness hazards in subexpressions.
DEGREE MODE IN MAGIC CALCULATOR FULL
Chapter 4: Full list of spigot's command line options.
0 kommentar(er)
