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Explicitly select items from a list or tuple
... myBigList[i] for i in [87, 342, 217, 998, 500] ]
20.6 usec: map(myBigList.__getitem__, (87, 342, 217, 998, 500))
22.7 usec: itemgetter(87, 342, 217, 998, 500)(myBigList)
24.6 usec: list( myBigList[i] for i in [87, 342, 217, 998, 500] )
Note that in Python 3, the 1st was changed to be the same as ...
What is this 'Lambda' everyone keeps speaking of?
... 'Lambda' everyone keeps speaking of? A lot of people seem to love it, but all I can gather from it is it is just a way of cramming lots of lines of code into a single expression.
...
Python argparse: Make at least one argument required
...
args = vars(parser.parse_args())
if not any(args.values()):
parser.error('No arguments provided.')
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receiving error: 'Error: SSL Error: SELF_SIGNED_CERT_IN_CHAIN' while using npm
... on ubuntu - I am receiving the error copied below while attempting to install any new modules via npm (I tested socket.io earlier using http, not https though & am wondering if that could have resulted in the issue with npm/unsigned certs). The error pops up once npm tries to resolve the ' https:/...
Impossible to Install PG gem on my mac with Mavericks
I'm trying to install the pg gem in order to work again with my rails projects. But I get this error:
26 Answers
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Download file from an ASP.NET Web API method using AngularJS
...he requested file simply by using the code below, and this is supported in all browsers, and will obviously trigger the WebApi request just the same.
$scope.downloadFile = function(downloadPath) {
window.open(downloadPath, '_blank', '');
}
Ajax binary download method:
Using ajax to downlo...
Difference between “git checkout ” and “git checkout -- ”
...his is not Git-specific, it's a general Unix command line convention. Normally you use it to clarify that an argument is a file name rather than an option, e.g.
rm -f # does nothing
rm -- -f # deletes a file named "-f"
git checkout1 also takes -- to mean that subsequent arguments are not ...
How to read a file in reverse order?
...A correct, efficient answer written as a generator.
import os
def reverse_readline(filename, buf_size=8192):
"""A generator that returns the lines of a file in reverse order"""
with open(filename) as fh:
segment = None
offset = 0
fh.seek(0, os.SEEK_END)
file...
How to rename a single column in a data.frame?
...r.name'
This code pretty much does the following:
names(df) looks into all the names in the df
[names(df) == old.var.name] extracts the variable name you want to check
<- 'new.var.name' assigns the new variable name.
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How to generate keyboard events in Python?
...om ctypes import wintypes
import time
user32 = ctypes.WinDLL('user32', use_last_error=True)
INPUT_MOUSE = 0
INPUT_KEYBOARD = 1
INPUT_HARDWARE = 2
KEYEVENTF_EXTENDEDKEY = 0x0001
KEYEVENTF_KEYUP = 0x0002
KEYEVENTF_UNICODE = 0x0004
KEYEVENTF_SCANCODE = 0x0008
MAPVK_VK_TO_VSC = 0
# ...