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Error when trying vagrant up

... Gar, that was it. Why does it say "You are now ready to vagrant up your first virtual environment!" then?? – Matt Jun 30 '15 at 21:55 ...
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Multiple glibc libraries on a single host

...of glibc on the same system (we do that every day). However, you need to know that glibc consists of many pieces (200+ shared libraries) which all must match. One of the pieces is ld-linux.so.2, and it must match libc.so.6, or you'll see the errors you are seeing. The absolute path to ld-linux.so....
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What key shortcuts are to comment and uncomment code?

...ss that these are the defaults, at least in the C++ defaults, but I don't know for sure. The best way to find out is to check your settings.) share | improve this answer | f...
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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?

...ou're on 9.5 and don't need to be backward-compatible you can stop reading now. 9.4 and older: PostgreSQL doesn't have any built-in UPSERT (or MERGE) facility, and doing it efficiently in the face of concurrent use is very difficult. This article discusses the problem in useful detail. In general y...
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“Large data” work flows using pandas

... store.append(g, frame, index=False, data_columns = v['dc']) Now you have all of the tables in the file (actually you could store them in separate files if you wish, you would prob have to add the filename to the group_map, but probably this isn't necessary). This is how you get colum...
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How can I programmatically determine if my app is running in the iphone simulator?

As the question states, I would mainly like to know whether or not my code is running in the simulator, but would also be interested in knowing the specific iphone version that is running or being simulated. ...
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Can someone give an example of cosine similarity, in a very simple, graphical way?

...e than Linda loves me Jane likes me more than Julie loves me We want to know how similar these texts are, purely in terms of word counts (and ignoring word order). We begin by making a list of the words from both texts: me Julie loves Linda than more likes Jane Now we count the number of times ...
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How to return an empty ActiveRecord relation?

...and it takes an argument, depending on the value of the argument, I might know that there will not be any matches, but I still want to return a relation, not an empty array: ...
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Can javax.persistence.Query.getResultList() return null?

...t it right? No matter what, I would code defensively and check for null. Now the big question: should we treat "null" and an empty List as synonymous? This is where the specs should help us, and don't. My guess is that a null return (if indeed it could happen) would be equivalent to "I didn't un...
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Moment.js - how do I get the number of years since a date, not rounded up?

...on's age using Moment.js , but I'm finding that the otherwise useful fromNow method rounds up the years. For instance, if today is 12/27/2012 and the person's birth date is 02/26/1978, moment("02/26/1978", "MM/DD/YYYY").fromNow() returns '35 years ago'. How can I make Moment.js ignore the numbe...