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Sum a list of numbers in Python
...does integer division: it discards the remainder. To divide things through all the way, we need to use floating-point numbers. Fortunately, dividing an int by a float will produce a float, so we just use 2.0 for our divisor instead of 2.
Thus:
averages = [(x + y) / 2.0 for (x, y) in zip(my_list[:-...
Can I grep only the first n lines of a file?
... Is there a way to do this when using grep's -l option? I'd like to list all the files who's first 5 characters are RIFFD.
– James M. Lay
May 23 '17 at 19:20
add a comment
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rbenv not changing ruby version
I installed rbenv according to the github directions. I am running OSX but I have tried this on a Ubuntu 12.04 VM and got the same results. The following is what i get in my terminal when I try to change ruby versions:
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Maintain aspect ratio of div but fill screen width and height in CSS?
...t units vw and vh (viewport width / viewport height)
FIDDLE
Resize vertically and horizontally and you'll see that the element will always fill the maximum viewport size without breaking the ratio and without scrollbars!
(PURE) CSS
div
{
width: 100vw;
height: 56.25vw; /* height:width ra...
How do you check “if not null” with Eloquent?
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Actually here 'and' does nothing but it would do if first parameter would be an array. Here is the method prototype : public function where($column, $operator = null, $value = null, $boolean = 'and'); and location - ".....\vendor...
How Can I Set the Default Value of a Timestamp Column to the Current Timestamp with Laravel Migratio
...r considered a valid date. As documented at the Laravel 5.2 upgrade guide, all timestamp columns should receive a valid default value when you insert records into your database. You may use the useCurrent() column modifier (from Laravel 5.1.25 and above) in your migrations to default the timestamp ...
Java client certificates over HTTPS/SSL
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Finally solved it ;). Got a strong hint here (Gandalfs answer touched a bit on it as well). The missing links was (mostly) the first of the parameters below, and to some extent that I overlooked the difference between keystores ...
WPF: Setting the Width (and Height) as a Percentage Value
...ignment="Stretch" ...
That will make the Textbox element stretch horizontally and fill all the parent space horizontally (actually it depends on the parent panel you're using but should work for most cases).
Percentages can only be used with grid cell values so another option is to create a grid ...
Can you autoplay HTML5 videos on the iPad?
...ugh both script and attribute implementations.
In Safari, on iOS (for all devices, including iPad), where the user may be on a cellular network and be charged per data unit, preload and
auto-play are disabled. No data is loaded until the user initiates it." - Apple documentation.
Here is a ...
How to show “if” condition on a sequence diagram?
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If else condition, also called alternatives in UML terms can indeed be represented in sequence diagrams. Here is a link where you can find some nice resources on the subject
http://www.ibm.com/developerworks/rational/library/3101.html
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