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Convert a row of a data frame to vector
...u have to be careful if your row contains a factor. Here is an example:
df_1 = data.frame(V1 = factor(11:15),
V2 = 21:25)
df_1[1,] %>% as.numeric() # you expect 11 21 but it returns
[1] 1 21
Here is another example (by default data.frame() converts characters to factors)
d...
How to import a Python class that is in a directory above?
...ithout any necessary relationship to packaging -- then you need to work on __file__ to find out the parent directory (a couple of os.path.dirname calls will do;-), then (if that directory is not already on sys.path) prepend temporarily insert said dir at the very start of sys.path, __import__, remov...
Ruby replace string with captured regex pattern
... note that you can index a string with a regex:
"foo"[/oo/]
#=> "oo"
"Z_123: foobar"[/^Z_.*(?=:)/]
#=> "Z_123"
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What is the JavaScript equivalent of var_dump or print_r in PHP? [duplicate]
...e of object in JavaScript (for debugging). Is there anything similar to var_dump in PHP?
9 Answers
...
Characters allowed in a URL
...738 specification:
Thus, only alphanumerics, the special characters "$-_.+!*'(),", and
reserved characters used for their reserved purposes may be used
unencoded within a URL.
EDIT: As @Jukka K. Korpela correctly points out, this RFC was updated by RFC 3986.
This has expanded and clarified...
Passing parameters to a Bash function
...s of declaring a function. I prefer the second approach.
function function_name {
command...
}
or
function_name () {
command...
}
To call a function with arguments:
function_name "$arg1" "$arg2"
The function refers to passed arguments by their position (not by name), that is $1, $2...
define() vs. const
... a static scalar (number, string or other constant like true, false, null, __FILE__), whereas define() takes any expression. Since PHP 5.6 constant expressions are allowed in const as well:
const BIT_5 = 1 << 5; // Valid since PHP 5.6 and invalid previously
define('BIT_5', 1 << 5); /...
What are the best JVM settings for Eclipse? [closed]
...clipse.platform
--launcher.defaultAction
openFile
-vm
C:/Prog/Java/jdk1.6.0_21/jre/bin/server/jvm.dll
-vmargs
-Dosgi.requiredJavaVersion=1.6
-Declipse.p2.unsignedPolicy=allow
-Xms128m
-Xmx384m
-Xss4m
-XX:PermSize=128m
-XX:MaxPermSize=384m
-XX:CompileThreshold=5
-XX:MaxGCPauseMillis=10
-XX:MaxHeapFre...
What is “:-!!” in C code?
...ld.
The macro is somewhat misnamed; it should be something more like BUILD_BUG_OR_ZERO, rather than ...ON_ZERO. (There have been occasional discussions about whether this is a confusing name.)
You should read the expression like this:
sizeof(struct { int: -!!(e); }))
(e): Compute expression e....
How much faster is Redis than mongoDB?
...is()
mongo = Connection().test
collection = mongo['test']
collection.ensure_index('key', unique=True)
def mongo_set(data):
for k, v in data.iteritems():
collection.insert({'key': k, 'value': v})
def mongo_get(data):
for k in data.iterkeys():
val = collection.find_one({'key'...