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Test if string is a number in Ruby on Rails
...mber? string
true if Float(string) rescue false
end
And then call it like this:
my_string = '12.34'
is_number?( my_string )
# => true
Extend String Class.
If you want to be able to call is_number? directly on the string instead of passing it as a param to your helper function, then you n...
Swift Beta performance: sorting arrays
...ce was very poor. After digging deeper I realized that one of the bottlenecks was something as simple as sorting arrays. The relevant part is here:
...
Recommended date format for REST GET API
What's the recommended timestamp format for a REST GET API like this:
5 Answers
5
...
JPanel Padding in Java
...he sides and top, touching the colored borders: how can I add padding? Thank you.
4 Answers
...
Base64 Decoding in iOS 7+
...
Cœur
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answered Sep 30 '13 at 7:09
Gabriele Petron...
Deleting array elements in JavaScript - delete vs splice
...ject property, but will not reindex the array or update its length. This makes it appears as if it is undefined:
> myArray = ['a', 'b', 'c', 'd']
["a", "b", "c", "d"]
> delete myArray[0]
true
> myArray[0]
undefined
Note that it is not in fact set to the value undefined, rather the ...
Print a list in reverse order with range()?
...
It's much more meaningful.
Update:
If you want it to be a list (as btk pointed out):
list(reversed(range(10)))
Update:
If you want to use only range to achieve the same result, you can use all its parameters. range(start, stop, step)
For example, to generate a list [5,4,3,2,1,0], you can ...
Changes in import statement python3
...
Relative import happens whenever you are importing a package relative to the current script/package.
Consider the following tree for example:
mypkg
├── base.py
└── derived.py
Now, your derived.py requires something from base.py. In Python 2, you could do it like th...
How to install multiple python packages at once using pip
I know it's an easy way of doing it but i didn't find it neither here nor on google.
So i was curious if there is a way to install multiple packages using pip.
Something like:
...
How can I check that a form field is prefilled correctly using capybara?
...
You can use an xpath query to check if there's an input element with a particular value (e.g. 'John'):
expect(page).to have_xpath("//input[@value='John']")
See http://www.w3schools.com/xpath/xpath_syntax.asp for more info.
For perhaps a prettier way:
exp...