BC: Basic Calculator

Save settings for bc, the Linux calculator

Use a ~/.bc file with contents:

scale=6

Execute this or put it in your bashrc:

$ export BC_ENV_ARGS=~/.bc

Explanation

In GNU/Linux, a basic calculator is bc from package bc. The normal output is displayed with zero values after the decimal point, so I like to adjust it to show me four numerals past the decimal point.

scale=6

You can use whatever scale you like.

With GNU bc, you can set the environment variable BC_ENV_ARGS to be the name of a file that bc should read on startup.
Add the following to your .bashrc file :

$ export BC_ENV_ARGS=$HOME/.bc

… or, if you need to load the standard math library, you can do this :

$ export BC_ENV_ARGS="-l $HOME/.bc"

Sources:

Saving settings for bc
Command Line Calculator , BC
Wiki: Run commands
Ubuntu Help: Environment Variables
Man Page: BC