Category:Bc: Difference between revisions

'''bc''' is the standard calculator for [[Unix]] systems. bc boasts unlimited precision, to handle numbers with very many digits. With the bc language, you can write programs that perform numeric calculations and print the results. (See also [[wp:Bc programming language|Bc programming language]] on Wikipedia.)

bc has an interactive mode, which is convenient for brief calculations.

Division and <tt>sqrt</tt> will not give an infinite number of digits. The special variable <tt>scale</tt> controls when to stop.

bc language resembles [[C|C language]]: bc has most of the same operators and control structures ('if', 'while', 'for'). Expressions print themselves, unless they are assignments. The newline is a statement separator, like the semicolon.

bc has excellent numeric operations, but is a poor language. The original bc, the "Bell Calculator" of Unix V7, translated the program to [[dc]] and inherited the limitations of [[dc]].

Some newer implementations, like [[GNU bc]] and [[OpenBSD bc]], discard these silly limitations, but users can still feel their effects. OpenBSD says, "a = b < c is interpreted as "(a = b) < c, which is probably not what the programmer intended," and "!a < b is interpreted as !(a < b)".

bc can only print a string, and has no other string operations, so bc cannot do tasks like [[reverse a string]]. bc has no way to read user input, except to go to interactive mode after loading a program.