glenda.party

term% ls -F

term% cat index.txt

BC(1) General Commands Manual BC(1) NAME bc - arbitrary-precision arithmetic language SYNOPSIS bc [ -c ] [ -l ] [ file ... ] DESCRIPTION Bc is an interactive processor for a language which resembles C but provides unlimited precision arithmetic. It takes input from any files given, then reads the standard input. The -l argument stands for the name of an arbitrary precision math library. The syntax for bc pro‐ grams is as follows; L means letter a-z, E means expression, S means statement. Comments are enclosed in /* and */. Names simple variables: L array elements: L [ E ] The words `ibase', `obase', and `scale' Other operands arbitrarily long numbers with optional sign and decimal point. ( E ) sqrt ( E ) length ( E ) number of significant decimal digits scale ( E ) number of digits right of decimal point L ( E , ... , E ) Operators + - * / % ^ (% is remainder; ^ is power) ++ -- (prefix and postfix; apply to names) == <= >= != < > = =+ =- =* =/ =% =^ Statements E { S ; ... ; S } if ( E ) S while ( E ) S for ( E ; E ; E ) S null statement break quit Function definitions define L ( L ,..., L ) { auto L, ... , L S; ... S return ( E ) } Functions in -l math library s(x) sine c(x) cosine e(x) exponential l(x) log a(x) arctangent j(n,x) Bessel function All function arguments are passed by value. The value of a statement that is an expression is printed unless the main operator is an assignment. Either semicolons or newlines may sep‐ arate statements. Assignment to scale influences the number of digits to be retained on arithmetic operations in the manner of dc(1). As‐ signments to ibase or obase set the input and output number radix re‐ spectively. The same letter may be used as an array, a function, and a simple vari‐ able simultaneously. All variables are global to the program. `Auto' variables are pushed down during function calls. When using arrays as function arguments or defining them as automatic variables empty square brackets must follow the array name. For example scale = 20 define e(x){ auto a, b, c, i, s a = 1 b = 1 s = 1 for(i=1; 1==1; i++){ a = a*x b = b*i c = a/b if(c == 0) return(s) s = s+c } } defines a function to compute an approximate value of the exponential function and for(i=1; i<=10; i++) e(i) prints approximate values of the exponential function of the first ten integers. Bc is actually a preprocessor for dc(1), which it invokes automati‐ cally, unless the -c (compile only) option is present. In this case the dc input is sent to the standard output instead. FILES /usr/lib/lib.b mathematical library dc(1) desk calculator proper SEE ALSO dc(1) L. L. Cherry and R. Morris, BC - An arbitrary precision desk-calculator language BUGS No &&, ||, or ! operators. For statement must have all three E's. Quit is interpreted when read, not when executed. BC(1)