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List changes unexpectedly after assignment. How do I clone or copy it to prevent this?
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With new_list = my_list, you don't actually have two lists. The assignment just copies the reference to the list, not the actual list, so both new_list and my_list refer to the same list after the assignment.
To actually copy the list, you have various possibilit...
Find which version of package is installed with pip
..., is it possible to figure out which version of a package is currently installed?
15 Answers
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Split column at delimiter in data frame [duplicate]
...b','b|c','x|y'))
library(splitstackshape)
cSplit(df, "FOO", "|")
# ID FOO_1 FOO_2
# 1 11 a b
# 2 12 b c
# 3 13 x y
This particular function also handles splitting multiple columns, even if each column has a different delimiter:
df <- data.frame(ID=11:13,
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Vim: Replacing a line with another one yanked before
... If you overwrite additional lines with ccCTRL+r0ESC instead of V"0p then all following lines can be replaced with just . (the repeater)
– Jordan Morris
Aug 26 '13 at 5:10
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django change default runserver port
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You can't run the development server programmatically, so a custom command won't work unless it calls the shell using something like call. If this solution works for you please make sure to mark it as solved.
– Pablo Albornoz
May 13 '1...
$_POST vs. $_SERVER['REQUEST_METHOD'] == 'POST'
Some guy called one of my Snipplr submissions "crap" because I used if ($_SERVER['REQUEST_METHOD'] == 'POST') instead of if ($_POST)
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In PHP, can you instantiate an object and call a method on the same line?
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@CMCDragonkai logically that makes sense; the object only exists for the duration of the statement (new Foo)->property - the value you are storing has nowhere to go because the object will no longer exist after that as it's not stored anywhe...
Undefined symbols for architecture i386: _OBJC_CLASS_$_SKPSMTPMessage", referenced from: error
...r the "Compile Sources" step of the "Build Phases" tab of your target. Normally Xcode does this for you, but sometimes it loses the plot and you need to add the .m file manually.
To do this:
TargetSettings -> Build Phases -> Compile Sources -> add your .m class ->Build and Run
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UIButton Image + Text IOS
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I see very complicated answers, all of them using code. However, if you are using Interface Builder, there is a very easy way to do this:
Select the button and set a title and an image. Note that if you set the background instead of the image then the ima...
Downloading a picture via urllib and python
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Note for Python 3 it's actually import urllib.request urllib.request.urlretrieve("http://...jpg", "1.jpg"). It's urlretrieve now as of 3.x.
– user1032613
Mar 16 '18 at 0:18
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