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Get type of all variables
...R, I'd like to retrieve a list of global variables at the end of my script and iterate over them. Here is my code
6 Answers...
Best practices for in-app database migration for Sqlite
I am using sqlite for my iphone and I anticipate the database schema might change over time. What are the gotchas, naming conventions and things to watch out for to do a successful migration each time?
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Set cURL to use local virtual hosts
... applies, but simply pretends the DNS lookup returned the data in your command-line option. It works just like /etc/hosts should.
Note --resolve takes a port number, so for HTTPS you would use
curl --resolve 'yada.com:443:127.0.0.1' https://yada.com/something
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How to copy a selection to the OS X clipboard
...this might not work for you, but if you have Vim-version 7.4 then it does (and sometimes you don't even have to do the whole "+y ). And you check this by just writing >vim in the terminal and then the version-number is when you start it up.
– Zeth
Sep 9 '1...
Count(*) vs Count(1) - SQL Server
Just wondering if any of you people use Count(1) over Count(*) and if there is a noticeable difference in performance or if this is just a legacy habit that has been brought forward from days gone past?
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What is the advantage to using bloom filters?
I am reading up on bloom filters and they just seem silly. Anything you can accomplish with a bloom filter, you could accomplish in less space, more efficiently, using a single hash function rather than multiple, or that's what it seems. Why would you use a bloom filter and how is it useful?
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Intelligent point label placement in R
...ints (or other objects in the plot, but I see that this is much harder to handle).
7 Answers
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Codeigniter - no input file specified
I am a beginner in Codeigniter and I saw a CI tutorial and was just trying to do a simple thing. I downloaded the CI and added this file to controller directory, but it won't work.
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Does Java 8 provide a good way to repeat a value or function?
...- 1)
.forEach(System.out::println);
Or build a custom iteration and limit the size of the iteration:
IntStream.iterate(1, i -> i + 2)
.limit(8)
.forEach(System.out::println);
share
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How to concatenate twice with the C preprocessor and expand a macro as in “arg ## _ ## MACRO”?
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Standard C Preprocessor
$ cat xx.c
#define VARIABLE 3
#define PASTER(x,y) x ## _ ## y
#define EVALUATOR(x,y) PASTER(x,y)
#define NAME(fun) EVALUATOR(fun, VARIABLE)
extern void NAME(mine)(char *x);
$ gcc -E xx.c
# 1 "xx.c"
# ...