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Command line calculator

Terminal - Command line calculator
calc() { python -c "from math import *; print $1"; }
2010-10-07 08:26:39
User: asmaier
Functions: python
1
Command line calculator

This function defines a command line calculator that handles everything pythons math module can handle, e.g. trigonometric functions, sqrt, log, erf, ... (see http://docs.python.org/library/math.html). It even knows about the constants pi and e.

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
awk "BEGIN{ print $* }"
2010-10-07 16:13:41
User: maelcum
Functions: awk
4

works with fractions like 1/3.5

calc() { bc <<< $*; }
python -ic "from __future__ import division; from math import *; from random import *"
2011-10-24 19:47:27
User: fpunktk
Functions: python
1

This opens a python command line. You can use math and random and float-division is enabled (without appending .0 to integers). I just don't know how to specify a standard precision.

alias calc='python -ic "from math import *; from random import *"'
2011-10-24 08:15:41
User: Bonster
Functions: alias
0

use python as calculator, press ctrl+d to exit

reminder: when doing factions add atleast one decimal number like so

22.0/7 or 22/7.0

calc() { echo "scale=4; ${*//,/.}" | bc -l; }
2011-10-24 19:58:20
User: fpunktk
Functions: bc echo
-1

This is an "argument calculator" funktion. The precision is set to 4 and you can use dot (.) or comma (,) as decimal mark (which is great for german users with a comma on the numpad).

Know a better way?

If you can do better, submit your command here.

What others think

calc 3 +4

3

it must be print $*

Comment by hemanth 322 weeks and 2 days ago

Look for the sample output. You can see, that you are supposed to give the arguments in quotes!

> calc "3 +4"

7

Comment by asmaier 322 weeks and 2 days ago

@hemanth: Using $* does make some calculations easier. But if you're going to do multiplication, you'll need the wrap the whole expression (or the parts with '*' in them) in quotes. Otherwise, bash will expand the star and python will get confused.

Comment by aporter 322 weeks and 2 days ago

Your point of view

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