Just looking at something like your last example, this will replace a number with double its value:
s/\d\+/\=submatch(0) * 2/
This is known as a sub-replace expression and I go into some depth here, though with an emphasis on string operations: How to run a substitute command on only a certain part of the line
The key is \= which says "everything ...
You can use submatch() function and use it to substitute with some pattern on those lines may be.
I got it till here:
This replaces the lines where if finds the pattern that you requested for with YES.
Not sure how to do it without substitution.
Following for a ...
The following approach was not tested with Anaconda, but it fixed the issues for me when working with virtualenvwrapper
The vim-virtualenv plugin changes the executable and modifies sys.path and the $PATH environment.
I've compiled vim with python3.5, so when no virtualenv is activated I get:
:py3 import sys; print(sys.executable)