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How to join (merge) data frames (inner, outer, left, right)
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By using the merge function and its optional parameters:
Inner join: merge(df1, df2) will work for these examples because R automatically joins the frames by common variable names, but you would most likely want to specify merge(...
Number of occurrences of a character in a string [duplicate]
I am trying to get the number of occurrences of a certain character such as & in the following string.
6 Answers
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LINQ to Entities case sensitive comparison
This isn't a case-sensitive comparison in LINQ to Entities:
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Print content of JavaScript object? [duplicate]
... we just use alert(object); it will show as [object Object] . How to print all the content parameters of an object in JavaScript?
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ImportError: No module named Crypto.Cipher
...n I try to run app.py (Python 3.3, PyCrypto 2.6) my virtualenv keeps returning the error listed above. My import statement is just from Crypto.Cipher import AES . I looked for duplicates and you might say that there are some, but I tried the solutions (although most are not even solutions) and noth...
How to scale threads according to CPU cores?
I want to solve a mathematical problem with multiple threads in Java. my math problem can be separated into work units, that I want to have solved in several threads.
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Android and XMPP: Currently available solutions [closed]
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Smack
Smack is a open-source XMPP client library. Since version 4.1 it runs natively on Android. For more information have a look at the "Smack 4.3 Readme" and see the Smack project page at Ignite Realtime.
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Can't connect to localhost on SQL Server Express 2012 / 2016
... 2012 but I cannot connect to localhost. I tried localhost\SQLExpress and Windows authentication but it gives me an error message saying cannot connect. Am I missing something here? I've used SQL Server 2008 before and I've never had issues connecting to localhost. It seems that it can't even find i...
Easy interview question got harder: given numbers 1..100, find the missing number(s) given exactly k
I had an interesting job interview experience a while back. The question started really easy:
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pg_config executable not found
I am having trouble installing psycopg2. I get the following error when I try to pip install psycopg2 :
43 Answers
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