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What's the difference between integer class and numeric class in R
...t common of which are double (for double precision floating point numbers) and integer. R will automatically convert between the numeric classes when needed, so for the most part it does not matter to the casual user whether the number 3 is currently stored as an integer or as a double. Most math ...
How do I find a “gap” in running counter with SQL?
...n a counter column in an SQL table. For example, if there are values 1,2,4 and 5 I'd like to find out 3.
20 Answers
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Print all but the first three columns
...$(i-2)=$i; NF=NF-2; print $0}' | tr ' ' '-'
3-4-5-6-7
This is the fixed and parametrized version of larsr solution:
$ echo '1 2 3 4 5 6 7' |
awk '{for(i=n;i<=NF;i++)$(i-(n-1))=$i;NF=NF-(n-1);print $0}' n=4 | tr ' ' '-'
4-5-6-7
All other answers before Sep-2013 are nice but add extra spac...
How do you install Google frameworks (Play, Accounts, etc.) on a Genymotion virtual device? [duplica
I'm currently trying out Genymotion and boy, it's so much faster than the ADT emulator.
10 Answers
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How to set specific java version to Maven
On my machine I have two java versions installed: (1.6 and 1.7 installed manually by me). I need both of them for different projects. But for Maven I need 1.7, now my Maven uses 1,6 java version, how can I set Maven to use 1.7?
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Accessing the index in 'for' loops?
...on is to use the built-in function enumerate(), available in both Python 2 and 3:
for idx, val in enumerate(ints):
print(idx, val)
Check out PEP 279 for more.
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How to host a Node.Js application in shared hosting [closed]
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You can run node.js server on a typical shared hosting with Linux, Apache and PHP (LAMP). I have successfully installed it, even with NPM, Express and Grunt working fine. Follow the steps:
1) Create a new PHP file on the server with the following code and run it:
<?php
//Download and extract t...
Replace all 0 values to NA
...ays in ?'NULL',
NULL represents the null object in R
which is unique and, I guess, can be seen as the most uninformative and empty object.1 Then it becomes not so surprising that
data.frame(x = c(1, NULL, 2))
# x
# 1 1
# 2 2
That is, R does not reserve any space for this null object.2 Mea...
How do we control web page caching, across all browsers?
...he correct minimum set of headers that works across all mentioned clients (and proxies):
Cache-Control: no-cache, no-store, must-revalidate
Pragma: no-cache
Expires: 0
The Cache-Control is per the HTTP 1.1 spec for clients and proxies (and implicitly required by some clients next to Expires). The...
Error - trustAnchors parameter must be non-empty
I'm trying to configure my e-mail on Jenkins/Hudson, and I constantly receive the error:
44 Answers
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