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What is the difference between a var and val definition in Scala?
What is the difference between a var and val definition in Scala and why does the language need both? Why would you choose a val over a var and vice versa?
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How to match, but not capture, part of a regex?
...receded by 123- and followed by 456.
|Lookaround | Name | What it Does |
-----------------------------------------------------------------------
|(?=foo) | Lookahead | Asserts that what immediately FOLLOWS the |
| | | current pos...
Convert Python dict into a dataframe
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@user1009091 I realised what the error means now, it's basically saying "What I'm seeing is a Series, so use Series constructor".
– Andy Hayden
Sep 16 '13 at 21:16
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Check if database exists in PostgreSQL using shell
...turo's solution:
psql -lqt | cut -d \| -f 1 | grep -qw <db_name>
What it does
psql -l outputs something like the following:
List of databases
Name | Owner | Encoding | Collate | Ctype | Access privileges
-----------+---------...
Check if the number is integer
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What's wrong with as.integer(x) == x? It will not reject 3 or 3.0 like is.integer(x) would, and it will catch 3.1.
– Gabi
Oct 1 '15 at 19:04
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How do I check if a string is a number (float)?
What is the best possible way to check if a string can be represented as a number in Python?
33 Answers
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Vertically align text to top within a UILabel
...nging the label's frame. I've made my labels orange so you can see clearly what's happening.
Here's the quick and easy way to do this:
[myLabel sizeToFit];
If you have a label with longer text that will make more than one line, set numberOfLines to 0 (zero here means an unlimited number ...
Why doesn't Internet Explorer 11 honour conditional comments even when emulating Internet Explorer 8
...ring" with stuff just when users are starting to get used to them. Look at what they did to Windows XP... "Fixing what's not broken", some people would say. Anyway that sucks
– Rolf
Nov 29 '13 at 6:24
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Is 'switch' faster than 'if'?
...s and many cases against values in said enumeration. That said, I stand by what I said above in 2011 -- too often I see people thinking "if I make it a switch, it'll be the same time no matter how many cases I have" -- and that's completely false. Even with a jump table you get the indirect jump cos...
Complete Working Sample of the Gmail Three-Fragment Animation Scenario?
TL;DR: I am looking for a complete working sample of what I'll refer to as "the Gmail three-fragment animation" scenario. Specifically, we want to start with two fragments, like this:
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