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How to find keys of a hash?
...
There is function in modern JavaScript (ECMAScript 5) called Object.keys performing this operation:
var obj = { "a" : 1, "b" : 2, "c" : 3};
alert(Object.keys(obj)); // will output ["a", "b", "c"]
Compatibility details can be found here.
On the Mozilla site there is also a sn...
In JavaScript, why is “0” equal to false, but when tested by 'if' it is not false by itself?
...e special [[Get]] internal method defined below.
b. Return the result of calling the get internal method using base as its this value, and passing
GetReferencedName(V) for the argument
Or in other words, a string has a primitive base, which calls back the internal get method and ends up looking ...
How to make a Python script run like a service or daemon in Linux
...ass the Daemon class and override the run() method
"""
def __init__(self, pidfile, stdin='/dev/null', stdout='/dev/null', stderr='/dev/null'):
self.stdin = stdin
self.stdout = stdout
self.stderr = stderr
self.pidfile = p...
How do I parse a string to a float or int?
...
Python method to check if a string is a float:
def is_float(value):
try:
float(value)
return True
except:
return False
A longer and more accurate name for this function could be: is_convertible_to_float(value)
What is, and is not a float in Python may surpris...
CSS: Change image src on img:hover
... <img src="https://cdn4.iconfinder.com/data/icons/imoticons/105/imoticon_15-128.png" />
<img src="https://cdn4.iconfinder.com/data/icons/imoticons/105/imoticon_12-128.png" />
</a>
CSS
a img:last-child {
display: none;
}
a:hover img:last-child {
display: block;
}
a:ho...
WARNING: Can't verify CSRF token authenticity rails
... that you have <%= csrf_meta_tag %> in your layout
Add beforeSend to all the ajax request to set the header like below:
$.ajax({ url: 'YOUR URL HERE',
type: 'POST',
beforeSend: function(xhr) {xhr.setRequestHeader('X-CSRF-Token', $('meta[name="csrf-token"]').attr('content'))},
data: '...
Getting the object's property name
...
More specifically, Object.keys(obj) returns an array of property names, i.e. keys, belonging to the passed in obj.
– a learner has no name
Mar 26 '16 at 12:43
...
Reshaping data.frame from wide to long format
...s melt/cast. Here is a solution with reshape, assuming your data frame is called d:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
timevar = "Year",
times = 1950:1954)
...
Regex - Should hyphens be escaped? [duplicate]
...
Correct on all fronts. Outside of a character class (that's what the "square brackets" are called) the hyphen has no special meaning, and within a character class, you can place a hyphen as the first or last character in the range (e.g....
How to show math equations in general github's markdown(not github's blog)
...portant word being "secure" there, considering your question :).
Indeed, allowing javascript to be executed would be a bit off of the MarkDown standard text-to-HTML contract.
Moreover, everything that looks like a HTML tag is either escaped or stripped out.
Tell me how to show math symbols in...