abacus

Abacus is a simple interactive calculator CLI with support for variables, comparison checks, and math functions

λ ./abacus -h         
abacus - a simple interactive calculator CLI with support for variables, 
comparison checks, and math functions

v1.0.0

Usage: abacus [--no-color] [--precision PRECISION] [--eval EVAL]

Options:
  --no-color, -n         disable color in output [default: false]
  --precision PRECISION, -p PRECISION
                         precision for calculations [default: 64]
  --eval EVAL, -e EVAL   evaluate expression and quit
  --help, -h             display this help and exit
  --version              display version and exit

Install

go get -u github.com/viktordanov/abacus

Features

• History of expressions and Tab completion of all math functions and defined variables
• All common operations

  > 1+1
  2
  > 1-20
  -19
  > 5^0 / 20
  0.05
  > 2**(2+5)
  128
  

• Variables

  > d = 12.5
  12.5
  > d * 5 + 5
  67.5
  > a * 5 + 5
  5
  

  Note: Undefined variables are equal to 0
• Comparisons <, ==, >, <=, >=

  > pi > phi
  true
  > 10 <=10
  true
  > 2 == 0
  false
  

• E, Pi, Phi

  > e
  2.7182818284590450907955982984276
  > pi
  3.1415926535897931159979634685442
  > phi
  1.6180339887498949025257388711907
  

• Single arity functions:
  • sqrt
  • ln
  • floor
  • ceil
  • exp
  • sin
  • cos
  • tan
  • round
• Two arity functions:
  • round (number, digits of precision)

  > round(1.123456789,4)
  1.123
  

  • log (number, base)

  > log(16,4)
  2
  

  • min, max

  > d = 10
  10 
  > min(d,4)
  4
  > max(d,4)
  10
  

Reserved names

• quit – If a query includes quit, the program will terminate and the query will not be saved to the history file
• The constants e, pi, and phi

TODO

• Add full feature list
• Write tests
  • Base tests
  • Simple benchmark of a complicated expression
  • Improve tests
• Refactor to depend less on other packages
• Implement most single arity functions with *big.Float for improved precision