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Double vs single quotes
I'm really new to Ruby and I'm trying to understand if there's a specific time when I should use "" vs '' .
8 Answers
...
Split array into chunks
...his answer):
More efficient method:
// refresh page if experimenting and you already defined Array.prototype.chunk
Object.defineProperty(Array.prototype, 'chunk', {
value: function(chunkSize) {
var R = [];
for (var i = 0; i < this.length; i += chunkSize)
R.push(this.s...
Send attachments with PHP Mail()?
...cript from here: http://github.com/PHPMailer/PHPMailer
Extract the archive and copy the script's folder to a convenient place in your project.
Include the main script file -- require_once('path/to/file/class.phpmailer.php');
Now, sending emails with attachments goes from being insanely difficult t...
Multiline strings in JSON
I'm writing some data files in JSON format and would like to have some really long string values split over multiple lines. Using python's JSON module I get a whole lot of errors, whether I use \ or \n as an escape.
...
'printf' vs. 'cout' in C++
What is the difference between printf() and cout in C++?
16 Answers
16
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How do I prompt for Yes/No/Cancel input in a Linux shell script?
I want to pause input in a shell script, and prompt the user for choices.
The standard Yes , No , or Cancel type question.
How do I accomplish this in a typical bash prompt?
...
pyplot scatter plot marker size
...ases it by a factor of 4). To see this consider the following two examples and the output they produce.
# doubling the width of markers
x = [0,2,4,6,8,10]
y = [0]*len(x)
s = [20*4**n for n in range(len(x))]
plt.scatter(x,y,s=s)
plt.show()
gives
Notice how the size increases very quickly. If in...
Create numpy matrix filled with NaNs
...oops for vector operations in numpy.
You can create an uninitialized array and assign to all entries at once:
>>> a = numpy.empty((3,3,))
>>> a[:] = numpy.nan
>>> a
array([[ NaN, NaN, NaN],
[ NaN, NaN, NaN],
[ NaN, NaN, NaN]])
I have timed the alte...
PostgreSQL: Difference between text and varchar (character varying)
What's the difference between the text data type and the character varying ( varchar ) data types?
9 Answers
...
How does Duff's device work?
I've read the article on Wikipedia on the Duff's device , and I don't get it. I am really interested, but I've read the explanation there a couple of times and I still don't get it how the Duff's device works.
...