rca -- a rich/RPN scientific and programmer's calculator
  Any arguments on the command line are used as initial calculator input.
  Entering a number pushes it on the stack.
  Operators replace either one or two stack values with their result.
  Most whitespace is optional between numbers and operators.
  Input can include locale currency and digit grouping symbols (e.g. $12,345)
  Always prefix hex ("0x7f") or octal ("0o177"), even in hex or octal mode.
  Infix expressions are entered using (...), as in: (sin(30)^2 + cos(30)^2)
  Below, 'x' refers to top-of-stack, 'y' refers to the next value beneath.
  rca's normal exit value reflects the logical value of the top of stack.

 Numeric
  (2 operands)
                 +, -     Add and subtract x and y
              *, or x     Multiply x and y
               /, mod     Divide and modulo of y by x
             ^, or **     Raise y to the x'th power
            %, +%, -%     x% of y, and y +/- x% of y
                   %?     what percent of y is x?
  (1 operand)
       chs, or negate     Change sign of x (2's complement)
          recip, sqrt     Reciprocal and square root of x
        sin, cos, tan
     asin, acos, atan     Trig functions
                atan2     Arctan of y/x (2 operands)
                  exp     Raise e to the x'th power
      ln, log2, log10     Natural, base 2, and base 10 logarithms
       abs, frac, int     Absolute value, fractional and integer parts of x

 Bitwise
  (2 operands)
               >>, <<     Shift y right/left by x bits (logical shift)
             ror, rol     Rotate y right/left by x bits
            &, |, xor     Bitwise AND, OR, and XOR of y and x
         setb, clearb     Set and clear bit x in y
  (1 operand)
                    ~     Bitwise NOT of x (1's complement)
                 bitc     Count of '1' bits in x

 Logical
  (mostly 2 operands)
               &&, ||     Logical AND and OR
 ==, !=, <, <=, >, >=     Arithmetic comparisons
                    !     Logical NOT of x

 Unit conversions
  (1 operand)
           i2mm, mm2i     inches / millimeters
           ft2m, m2ft     feet / meters
         mi2km, km2mi     miles / kilometers
             f2c, c2f     degrees F/C
           oz2g, g2oz     US ounces / grams
         oz2ml, ml2oz     US fluid ounces / milliliters
             q2l, l2q     US quarts / liters
             d2r, r2d     degrees / radians
       dd2dms, dms2dd     decimal degrees / deg.mm.sss
           mpg2l100km     mpg to l/100km and vice versa

 Constants and storage
             sto, rcl     Save to or push from off-stack storage
                pi, e     Push constant pi or e
 lastx, lasty, lx, ly     Push previous value of x or y
              _<name>     Push variable
                    =     Assign variable.  RPN: "3 = _v"   infix: "(_v = 3)"
   variables, or vars     Show the current list of variables
       clearvariables     Discard all variables

 Variadic
  (use whole stack, or to mark, if set)
                 mark     Mark the stack, to limit variadics' range
     sum, avg, stddev     Total, mean, and standard deviation of entries
             snapshot     Saves copy of selected entries
              restore     Push a copy of the snapshot, set mark
        clearsnapshot     Discard snapshot

 Stack manipulation
                clear     Clear stack
                  pop     Pop (and discard) x
         push, or dup     Push (a duplicate of) x
        exch, or swap     Exchange x and y

 Other
              (, ;, )     Infix expression grouping
                    :     Treat rest of line as RPN. (for infix mode)
                  nop     Does nothing, but at end of line, suppresses output

 Display
                    P     Print whole stack according to mode
                    p     Print x according to mode
              f, c, m     Print x as float, currency, max float (30 digits),
        d, u, h, o, b        decimal, unsigned, hex, octal, or binary
   automatic, or auto     Select general purpose floating display format
  engineering, or eng     Select engineering style floating display format
                fixed     Select fixed decimal floating display format
               digits     Set number of digits for floating formats

 Modes
                 F, C     Switch to floating or currency mode
           D, H, O, B     Switch to decimal, hex, octal, binary mode
       width, or bits     Set effective word size for integer modes
      zerofill, or zf     Toggle left-fill with zeros in H, O, and B modes
    rightalign, or ra     Toggle right alignment of numbers
              degrees     Toggle trig functions: degrees (1) or radians (0)
     autoprint, or ap     Toggle autoprinting on/off with 0/1
   separators, or sep     Toggle numeric separators on/off (0/1)
                 mode     Display current mode parameters
                infix     Toggle running mainly in infix, or in RPN

 Housekeeping
           ?, or help     Show this list (using $PAGER, if set)
               config     Show current configuration settings
                state     Show calculator state
           precedence     List infix operator precedence
     quit, q, or exit     Leave the calculator
                 echo     Toggle echoing input when stdin is file or pipe
            errorexit     Toggle exiting on errors and warnings
                debug     Toggle visibility of debug/testing commands
              license     Display the rca copyright and license.
              version     Show program version
                    #     Comment. The rest of the line will be ignored.


                                                   version v43     Apr 9, 2026

 Tip:	Use "rca help q | less" to view this help