wcalc - a natural-expression command-line calculator

wcalc [ options ] [ expression ... ]

wcalc is a command-line calculator designed to accept all valid mathematical expressions. It supports all standard mathematical operations, parenthesis, brackets, trigonometric functions, hyperbolic trig functions, logs, and boolean operators.

If no mathematical expression is given at the commandline, wcalc enters "interactive" mode. Interactive mode has more features. Also, files may be piped to wcalc, and they will be interpreted.

Variables are supported and may be assigned using the = operator. To assign a variable use the form: foo = anylegalexpression Thereafter, that variable name is the same as the literal value it represents. Expressions can be stored in variables like this: "foo = 'anylegalexpression' Expressions stored this way will be interpreted at evaluation time, rather than assignment-time. Note that these cannot be recursive.

OPTIONS

The functions supported in wcalc are almost all self-explanatory. For those few that are not, here is a full description.

sin cos tan cot

The standard trigonometric functions

asin acos atan acot or arcsin arccos arctan arccot or sin^-1 cos^-1 tan^-1 cot^-1

The standard arc- trigonometric functions.

sinh cosh tanh coth

The standard hyperbolic trigonometric functions.

asinh acosh atanh acoth or arcsinh arccosh arctanh arccoth or sinh^-1 cosh^-1 tanh^-1 coth^-1

The standard arc- hyperbolic trigonometric functions.

log ln logtwo

Log-base-ten, log-base-e and log-base-two, respectively. Remember, you can also construct log-base-X of number Y by computing log(Y)/log(X).

round

Returns the integral value nearest to the argument according to the typical rounding rules.

abs

Returns the absolute value of the argument.

ceil ceiling floor

Returns the ceiling or floor of the argument.

sqrt cbrt

The square and cube root functions.

rand

Returns a random number between 0 and the number given.

irand

Returns a random integer between 0 and the number given.

fact

Returns the factorial of a number.

Wcalc supports a lot of constants. Some are special (like pi), and some are simply mathematical or physical constants that have been hardcoded in. The physics constants are taken from http://physics.nist.gov/constants, and should all be in predictable SI units.

The value of pi is special, as it is calculated to however many bits of precision have been specified with the \bits command. The default number of bits is 1024, or a value of:

3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679821480865132823066470938446095505822317253594081284811174502841027019385211055596446229489549303819644288109756659334461284756482337867831652712019091456485669234603486104543266482133936072602491412737245869974724822361502823407955151120558811684656967313093357387193011055974127397801166600823447367841524950037348489795545416453901986117572722731871388422643588974212021713194956805142308399313566247553371620129340026051601856684677033122428187855479365508702723110143458240736806341798963338923286460351089772720817919599675133363110147505797173662675795471777702814318804385560929672479177350549251018537674006123614790110383192502897923367993783619310166679013187969315172579438604030363957033826325935372151289640167976948453904619615481368332936937026831888367580239969088932697527811653282224950410336573385944190516446146423694037380609059088222036945727944116946240616684848934170304346480406820774078369140625

Similarly, all values that rely on the value of pi, like mu0, have the same level of precision. Here is a complete list of the symbols used to represent the constants hardcoded into wcalc:

e

The logarithm constant:

2.718281828459045235360287471352662497757247093699959574966

gamma

Euler's Constant: 0.57721566490153286060651209008240243104215933593992359880576723488486772677766467093694706329174674951463144724980708248096050401448654283622417399764492353625350033374293733773767394279259525824709491600873520394816567

g

Acceleration due to gravity: 9.80665 m/s/s

Cc

Coulomb's Constant: 8987551787.37

Universal Constants

Electromagnetic Constants

Atomic and Nuclear Constants

Physio-Chemical Constants

Random Constants

There are several commands that are supported in wcalc.

\pXXX

Sets the precision to XXX. This setting only affects output, not internal representations. A setting of -1 means formats output in whatever precision seems appropriate.

\e or \eng or \engineering

Toggles the formatting of output between decimal and scientific notation.

\help or ?

Displays a help screen.

\prefs

Prints out the current preference settings.

\li or \list or \listvars

Prints out the currently defined variables.

\r or \radians

Toggles between using and not using radians for trigonometric calculations.

\cons or \conservative

Toggles precision guards. Because of the way floating point numbers are stored, some operations, like 1-.9-.1, can return an extremely small number that is not zero but is less than the official precision of the floating point number and thus for all intents and purposes, it is 0. The precision guard will round numbers to zero if they are less than the official precision of the floating point number. However, sometimes numbers that small or smaller need to be displayed, and thus the precision guard should be turned off.

\p or \picky or \l or \lenient

Toggles variable parsing rules. When wcalc is "picky" it will complain if you use undefined variables. If it is "lenient", wcalc will assume a value of 0 for undefined variables.

\re or \remember or \remember_errors

Toggles whether or not expressions that produce errors are remembered in the history.

\pre or \prefix or \prefixes

Toggles the display of prefixes for hexadecimal, octal, and binary output.

\b or \bin or \binary

Results are printed in binary (base 2). Numbers printed in binary have a prefix of 0b unless the \prefixes command is used.

\d or \dec or \decimal

Results are printed in decimal (base 10). This option is the default, and does not have a default prefix to indicate that numbers are in base 10.

\h or \x or \hex or \hexadecimal

Results are printed in hexadecimal (base 16). Numbers printed in hexadecimal have a prefix of 0x unless the \prefixes command is used.

\o or \oct or \octal

Results are printed in octal (base 8). Numbers printed in octal have a prefix of 0 unless the \prefixes command is used.

\round none|simple|sig_fig

Wcalc can attempt to warn you when numbers have been rounded in the output display. It has two methods of keeping track---either by using significant figures (sig_fig), or by a simple digit-counting algorithm. Rounding in the command-line version is denoted by a tilde before the equals sign (~=). Rounding in the GUI version is denoted by changing the text color to red. In some cases, Wcalc may think that the number has been rounded even if it shouldn't have been necessary (this is because of the way floating point numbers are represented internally).

\dsepX

Sets the decimal separator character to be X.

\tsepX

Sets the thousands-place separator character to be X.

\hlimitX

Sets the limit (X) on the length of the history.

\openXXXXX

Loads file XXXXX.

\saveXXXXX

Saves the history and variable list to a file, XXXXX.

\bitsXXXX

Sets the number of bits of precision that will be used to internally represent numbers to be XXXX. The default is 1024. Set higher if you need more precision, set lower if you want to use less memory.

\ints

Toggles whether long integers will be abbreviated or not. This conflicts with engineering notation for large numbers, but not for decimals.

\prefs or \preferences

Displays the current preference settings.

\convert unit1 unit1

Converts the previous answer from unit1 to unit2.

wcalc is Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005 Kyle Wheeler.

It is freely distributed, and can be modified and used freely for any purpose, as long as a copy of the modification is sent to Kyle Wheeler at kyle-wcalc@memoryhole.net.

Any bugs found should be reported to

Kyle Wheeler at kyle-wcalc@memoryhole.net.