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How do I install an R package from source?
...nt me along this great tutorial on webscraping NYtimes with R . I would really love to try it. However, the first step is to installed a package called RJSONIO from source.
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How to check if one DateTime is greater than the other in C#
...swered Sep 18 '08 at 19:17
Jon GallowayJon Galloway
49k2424 gold badges118118 silver badges191191 bronze badges
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Rank function in MySQL
... (SELECT @curRank := 0) r
ORDER BY age;
The (SELECT @curRank := 0) part allows the variable initialization without requiring a separate SET command.
Test case:
CREATE TABLE person (id int, first_name varchar(20), age int, gender char(1));
INSERT INTO person VALUES (1, 'Bob', 25, 'M');
INSERT I...
how to stop browser back button using javascript
...
There are numerous reasons why disabling the back button will not really work. Your best bet is to warn the user:
window.onbeforeunload = function() { return "Your work will be lost."; };
This page does list a number of ways you could try to disable the back button, but none are guaranteed...
What are the special dollar sign shell variables?
... $3, ... are the positional parameters.
"$@" is an array-like construct of all positional parameters, {$1, $2, $3 ...}.
"$*" is the IFS expansion of all positional parameters, $1 $2 $3 ....
$# is the number of positional parameters.
$- current options set for the shell.
$$ pid of the current shell (...
“Too many values to unpack” Exception
...nATupleWithThreeValues()
print a
print b
raises
Traceback (most recent call last):
File "c.py", line 3, in ?
a,b = returnATupleWithThreeValues()
ValueError: too many values to unpack
Now, the reason why this happens in your case, I don't know, but maybe this answer will point you in the r...
Avoid browser popup blockers
...m javascript that is not invoked by direct user action. That is, you can call window.open in response to a button click without getting hit by the popup blocker, but if you put the same code in a timer event it will be blocked. Depth of call chain is also a factor - some older browsers only look a...
How to put multiple statements in one line?
...pproximate what you want.
As for the try ... except thing: It would be totally useless without the except. try says "I want to run this code, but it might throw an exception". If you don't care about the exception, leave away the try. But as soon as you put it in, you're saying "I want to handle a ...
Check list of words in another string [duplicate]
...
@Ockonal: and if you want to check that all words from that list are inside the string, just replace any() above with all()
– Nas Banov
Jul 17 '10 at 23:23
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How does BLAS get such extreme performance?
...e optimization. This boost significantly exceeds the second boost from parallelism and other hardware optimizations.
By the way, most (or even all) of the high performance BLAS implementations are NOT implemented in Fortran. ATLAS is implemented in C. GotoBLAS/OpenBLAS is implemented in C and i...