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Logical operators (“and”, “or”) in DOS batch
...an implicit conjunction.
IF Exist File1.Dat IF Exist File2.Dat GOTO FILE12_EXIST_LABEL
If File1.Dat and File1.Dat exist then jump the label FILE12_EXIST_LABEL.
See also: IF /?
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Setting environment variables on OS X
... extensive research and if you want to set variables that are available in all GUI applications, your only option is /etc/launchd.conf.
Please note that environment.plist does not work for applications launched via Spotlight. This is documented by Steve Sexton here.
Open a terminal prompt
Type su...
Random row selection in Pandas dataframe
... Thanks @eumiro. I also worked out that df.ix[np.random.random_integers(0, len(df), 10)] would also work.
– John
Apr 10 '13 at 10:58
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Dynamically adding a form to a Django formset with Ajax
I want to automatically add new forms to a Django formset using Ajax, so that when the user clicks an "add" button it runs JavaScript that adds a new form (which is part of the formset) to the page.
...
How do I uniquely identify computers visiting my web site?
..., fingerprints changed quite
rapidly, but even a simple heuristic was usually able to guess when a fingerprint was an “upgraded” version of a previously observed browser’s
fingerprint, with 99.1% of guesses correct and a false positive rate of only
0.86%.
We discuss what privacy thr...
import module from string variable
...
Finally, also remember that you can't import anything if there is no __init__.py in the folder with file you are trying to import.
– Seanny123
Dec 6 '13 at 7:31
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VIM Replace word with contents of paste buffer?
... the one that'd get overwritten by the change command.)
Registers are generally specified by typing " then the name (single character) of the register, like "ay then "ap to yank into register a, then put the contents of register a. Same goes for a change command. In this case, if you don't want the ...
What is the difference between screenX/Y, clientX/Y and pageX/Y?
...upper left. This point could be anywhere in the browser window and can actually change location if there are embedded scrollable pages embedded within pages and the user moves a scrollbar.
screenX and screenY:
Relative to the top left of the physical screen/monitor, this reference point only moves ...
How to set java_home on Windows 7?
...
Find JDK Installation Directory
First you need to know the installation path for the Java Development Kit.
Open the default installation path for the JDK:
C:\Program Files\Java
There should be a subdirectory like:
C:\Program Files\J...
How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...tionaries in a single expression?
For dictionaries x and y, z becomes a shallowly merged dictionary with values from y replacing those from x.
In Python 3.5 or greater:
z = {**x, **y}
In Python 2, (or 3.4 or lower) write a function:
def merge_two_dicts(x, y):
z = x.copy() # start with x's ...