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Python - write() versus writelines() and concatenated strings
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More specifically, writelines expects an iterable. You can use a list, a tuple, or a generator.
– Mark Ransom
Sep 11 '12 at 20:52
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When does static class initialization happen?
...tialized? If I never instantiate a class, but I access a static field, are ALL the static blocks and private static methods used to instantiate private static fields called (in order) at that instant?
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pandas: filter rows of DataFrame with operator chaining
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That is a really nice solution - I wasn't even aware that you could jury-rig methods like that in python. A function like this would be really nice to have in Pandas itself.
– naught101
Mar 3 '17 at...
Understanding the transclude option of directive definition?
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Consider a directive called myDirective in an element, and that element is enclosing some other content, let's say:
<div my-directive>
<button>some button</button>
<a href="#">and a link</a>
</div>
If...
Deleting an element from an array in PHP
...ndex the keys you can use \array_values() after unset() which will convert all keys to numerical enumerated keys starting from 0.
Code
<?php
$array = [0 => "a", 1 => "b", 2 => "c"];
unset($array[1]);
//↑ Key which you want to delete
?>
Output
[
[0] =&g...
RegEx to parse or validate Base64 data
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The simplest solution would be to strip out all whitespace (which is ignored as per the RFC) before validation.
– Ben Blank
Jan 24 '09 at 1:35
2
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Why are iframes considered dangerous and a security risk?
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As soon as you're displaying content from another domain, you're basically trusting that domain not to serve-up malware.
There's nothing wrong with iframes per se. If you control the content of the iframe, they're perfectly safe.
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Plotting a list of (x, y) coordinates in python matplotlib
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x, y = zip(*li) is really elegant python code! i've been doing the more straight-forward two lines of code with a list compression on each line (like the original question)
– Trevor Boyd Smith
Aug 23 '18 at ...
Bash script processing limited number of commands in parallel
... the exit status of the last
command waited for. If a job spec is given, all processes in the job
are waited for. If no arguments are given, all currently active child
processes are waited for, and the return status is zero. If neither
jobspec nor pid specifies an active child process of the...
Easiest way to check for an index or a key in an array?
... associative array)
[ ${array[key]+abc} ] && echo "exists"
Basically what ${array[key]+abc} does is
if array[key] is set, return abc
if array[key] is not set, return nothing
References:
See Parameter Expansion in Bash manual and the little note
if the colon is omitted, the ope...