IPython + Python: Single Bash Command
The following is a simple Bash function you can paste into your bashrc file to start Python/IPython depending on the context.
~/.bashrc
function python {
IPYTHON="/usr/bin/ipython"
PYTHON="/usr/bin/python"
if [[ -n $1 ]]; then
$PYTHON $@
elif [[ -e $IPYTHON ]]; then
$IPYTHON
else
$PYTHON
fi
}