## Issue

Under windows, when I need to perform a basic calculations, I use a built-in calculator. Now I would like to find out what is the common way if you only have a shell.

Thanks

## Solution

And you can always use the python interpreter, it’s normally included in linux distros.

http://docs.python.org/tutorial/introduction.html#using-python-as-a-calculator

```
$ python
Python 2.6.2 (r262:71605, Apr 14 2009, 22:40:02) [MSC v.1500 32 bit (Intel)]
Type "help", "copyright", "credits" or "license" for more information.
>>> 2+2
4
>>> # This is a comment
... 2+2
4
>>> 2+2 # and a comment on the same line as code
4
>>> (50-5*6)/4
5
>>> # Integer division returns the floor:
... 7/3
2
>>> 7/-3
-3
>>> # use float to get floating point results.
>>> 7/3.0
2.3333333333333335
```

The equal sign (‘=’) is used to assign a value to a variable. Afterwards, no result is displayed before the next interactive prompt:

```
>>> width = 20
>>> height = 5*9
>>> width * height
900
```

And of course there’s the math module which should solve most of your calculator needs.

```
>>> import math
>>> math.pi
3.1415926535897931
>>> math.e
2.7182818284590451
>>> math.cos() # cosine
>>> math.sqrt()
>>> math.log()
>>> math.log10()
```

Answered By – monkut

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