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TermCalc

An interactive command line calculator.

TermCalc is a scientific calculator that runs in your terminal.

Build & Install

TermCalc is written in Swift so you'll need a Swift compiler to build and install it.

To build and install the TermCalc binary run: 

git clone https://github.com/dmulholl/termcalc.git
cd termcalc
make release
make install

The binary will be installed as /usr/local/bin/termcalc.

You can find the source code on Github.

Usage

Run termcalc --help to view the command line help: 

Usage: termcalc

  TermCalc is an interactive command line calculator. All operations
  are performed using IEEE 754 64-bit floats.

Options:
  -d, --decimal <str>     Decimal separator (default '.').
  -k, --kilo <str>        Thousands separator (default: ',').
  -m, --milli <str>       Thousandths separator (default: ' ').
  -p, --precision <int>   Decimal precision of output (default: 9).

Flags:
  -h, --help              Print this help text and exit.
  -v, --version           Print the version number and exit.

Input

All mathematical operations are performed using IEEE 754 64-bit floats. Numbers can be entered in any of the following formats: 

123
123.456
0.123
.123

Exponential notation is also supported: 

1.23e4    ⟶   1.23 * 10 ^ 4    ⟶   12300
1.23e-4   ⟶   1.23 * 10 ^ -4   ⟶   0.000123

Binary, octal, decimal, and hexadecimal integer literals can be entered using a leading zero and letter prefix as below: 

0b101   ⟶   5
0o101   ⟶   65
0d101   ⟶   101
0x101   ⟶   257

You can use underscores to improve readability: 

pi = 3.141_592_654

Operators

The following mathematical operators are supported: 

+    addition
-    subtraction
*    multiplication
/    division
%    remainder
^    power
!    factorial

Expressions can be nested in brackets to override the standard precedence rules, e.g (3 + 4) * 5.

Variables

Variables are created by assigning to a name: 

foo = 2 + 3

Variable names can contain letters, underscores, and numbers, but must begin with either a letter or an underscore.

The following compound assignment operators are available for use with variables: +=, -=, *=, /=, %=, ^=. The expression: 

foo += 1

is equivalent to 

foo = foo + 1

Automatic Variables

The result of each evaluated expression is assigned to an automatic numbered variable: $1, $2, $3, etc. (This name is displayed beside the result.)

The result of the last expression is always available via the automatic variable $.

The mathematical constants pi and e are also available as preallocated variables.

Functions 

deg(x)        Convert x in radians to degrees.
rad(x)        Convert x in degrees to radians.

cos(x)        Cosine of x; x in radians.
sin(x)        Sine of x; x in radians.
tan(x)        Tangent of x; x in radians.

cosd(x)       Cosine of x; x in degrees.
sind(x)       Sine of x; x in degrees.
tand(x)       Tangent of x; x in degrees.

Aliases with an explicit r-for-radians suffix are also available: cosr, sinr, tanr. 

acos(x)       Inverse cosine of x; result in radians.
asin(x)       Inverse sine of x; result in radians.
atan(x)       Inverse tangent of x; result in radians.
atan(x,y)     Inverse tangent of y/x; result in radians,
              sign determined by the quadrant of (x,y).

acosd(x)      Inverse cosine of x; result in degrees.
asind(x)      Inverse sine of x; result in degrees.
atand(x)      Inverse tangent of x; result in degrees.
atand(x,y)    Inverse tangent of y/x; result in degrees,
              sign determined by the quadrant of (x,y).

Aliases with an explicit r-for-radians suffix are also available: acosr, asinr, atanr.

Longform (arccos) and shortform (acos) aliases are available for each function. 

cbrt(x)       Cube root of x.
root(n,x)     Principal n-th root of x.
sqrt(x)       Square root of x.

ln(x)         Natural log of x.
log(b,x)      Base-b log of x.
log2(x)       Base-2 log of x.
log10(x)      Base-10 log of x.

Keyboard Shortcuts

Standard line-editing keyboard shortcuts are supported: 

Ctrl-A    Move the cursor to the beginning of the line.
Ctrl-B    Move the cursor backwards.
Ctrl-C    Exit the application.
Ctrl-D    Delete the character at the cursor position.
Ctrl-E    Move the cursor to the end of the line.
Ctrl-F    Move the cursor forwards.
Ctrl-H    Delete the character to the left of the cursor.
Ctrl-K    Delete all characters to the right of the cursor.
Ctrl-L    Clear the screen.
Ctrl-U    Delete all characters to the left of the cursor.
Ctrl-W    Delete the previous word.
Ctrl-N    Scroll to the next history entry.
Ctrl-P    Scroll to the previous history entry.

The up and down arrow keys can also be used to scroll backwards and forwards through history entries.

License

Zero-Clause BSD (0BSD).