diff options
Diffstat (limited to 'man/1/fc')
| -rw-r--r-- | man/1/fc | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/man/1/fc b/man/1/fc new file mode 100644 index 00000000..8846f649 --- /dev/null +++ b/man/1/fc @@ -0,0 +1,182 @@ +.TH FC 1 +.SH NAME +fc \- command-line floating point calculator +.SH SYNOPSIS +.B fc +[ +.I base +] +.I expression +.br +.SH DESCRIPTION +.B Fc +calculates the result of its argument +.I expression +and prints the result in the format indicated by +the optional base argument. +.I Base +can be one of: +.TP +.B -d +Decimal, as produced by the +.B %g +format of +.IR sys-print (2). +.br +.TP +.B -x +Hexadecimal, prefixed with +.BR 0x . +.TP +.B -o +Octal, prefixed with +.BR 0 . +.TP +.B -b +Binary, prefixed with +.BR 0b . +.TP +.B -B +As +.BR -b , +but with extra lines to help bit-counting. +.TP +.BI -r\ radix +In base +.IR radix , +prefixed with +.IB \fR``\fPradix r\fR'',\fP +as understood by Limbo (e.g. +.BR 16r3fff ). +.TP +.B -c +As a unicode character, prefixed with +.BR @ . +.RE +.PP +.I Expression +is in reverse polish notation: +each command line argument is either an operand (number) or an operator. +Operands are pushed on a stack; operators pop items from +the stack (the number of items depends on the operator) +and push their result. All operands are converted to double precision +floating point numbers before being pushed. +Integer operations convert their operands to big (64-bit) integers. +When all arguments are exhausted, all the values currently +on the stack are printed, first-pushed first, in the specified +output format. +.PP +Operands can be given in any of the formats that +.I fc +can print, as detailed above. +.PP +When an operation is not commutative, the argument values +will be taken from the stack first-pushed first. +Most functions from from +.IR math-elem (2), +.IR math-fp(2) +are provided. +In addition, other provided operators include: +.TP +.B + - / x +Representing the four rules. Note the use of +.B x +rather than +.BR * , +to avoid clashes with shell metacharacters. +.br +.TP +.B xx +To the power. (equivelant to 'pow') +.br +.TP +.B rad deg +Convert value to or from radians. +.br +.TP +! +Factorial. +.br +.TP +.B _ +Unary minus. +.br +.TP +.B and or xor not +Bitwise operations. +.br +.TP +.B shl shr +Bitwise shift left/right. +.TP +.B p +Print the current top value on the stack. +.br +.TP +.B sum +Sum all the values currently pushed on the stack. +.br +.TP +.B swap +Swap the top two stack items. +.br +.TP +.B dup +Duplicate the top item on the stack. +.br +.TP +.B rep +Repeatedly execute the last operator until +there is only only one item left on the stack. +This is only valid for operators that take exactly two +arguments. +.RE +.PP +A few symbolic names for operands are recognised, including +.B pi +(or +.BR π ), +.BR e , +and +.BR macheps . +.SH EXAMPLES +.PP +fc 22 7 / +.PP +.nf + gives 3.1428571429 +.fi +.PP +fc -b 1 2 3 4 sum +.PP +.nf + gives 0b00001010 +.fi +.PP +fc 10 0b10 010 0x10 x rep 0xa00 swap - +.PP +.nf + gives 0 +.fi +.PP +fc -help +.PP +.nf + gives a usage summary, including a list of + the names of all the operators. +.fi +.ne 5 +.SH SEE ALSO +.IR math-fp (2), +.IR math-elem (2), +.IR sh-expr (1) +.SH DIAGNOSTICS +An error message is displayed if +an operator is called on a stack with +too few elements. This also causes +.I fc +to yield a non-null exit status. +.SH BUGS +The +.B -B +option will only work for fixed-width fonts. |