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Getting the first character of a string with $str[0]
...ng multibyte encodings (such as UTF-8). If you want to support that, use mb_substr(). Arguably, you should always assume multibyte input these days, so this is the best option, but it will be slightly slower.
share
...
Run an OLS regression with Pandas Data Frame
... I accidentally typed formulas instead and got weird error: TypeError: from_formula() takes at least 3 arguments (2 given)
– denfromufa
Nov 14 '16 at 18:19
...
Download attachments using Java Mail
...tain this filename: "../etc/passwd", or any other path: They can overwrite _ANY_ file on the system that this code has write access to!
// File f = new File("/tmp/" + bodyPart.getFileName());
FileOutputStream fos = new FileOutputStream(f);
byte[] buf = new byte[4096];
in...
How do I format a date in Jinja2?
...and print) the strftime() method in your template, for example
{{ car.date_of_manufacture.strftime('%Y-%m-%d') }}
Another, sightly better approach would be to define your own filter, e.g.:
from flask import Flask
import babel
app = Flask(__name__)
@app.template_filter()
def format_datetime(val...
Python list of dictionaries search
... 3.6.4, W7x64.
from random import randint
from timeit import timeit
list_dicts = []
for _ in range(1000): # number of dicts in the list
dict_tmp = {}
for i in range(10): # number of keys for each dict
dict_tmp[f"key{i}"] = randint(0,50)
list_dicts.append( dict_tmp )
d...
C++ equivalent of java's instanceof
...
Try using:
if(NewType* v = dynamic_cast<NewType*>(old)) {
// old was safely casted to NewType
v->doSomething();
}
This requires your compiler to have rtti support enabled.
EDIT:
I've had some good comments on this answer!
Every time you nee...
Can I load a UIImage from a URL?
...llpaper.net/iphone/img/app/i/p/iphone-4s-wallpapers-mobile-backgrounds-dark_2466f886de3472ef1fa968033f1da3e1_raw_1087fae1932cec8837695934b7eb1250_raw.jpg");
var err: NSError?
var imageData :NSData = NSData.dataWithContentsOfURL(url,options: NSDataReadingOptions.DataReadingMappedIfSafe, error...
What is the use of static variable in C#? When to use it? Why can't I declare the static variable in
...red. Let me explain this with an example:
class circle
{
public float _PI =3.14F;
public int Radius;
public funtionArea(int radius)
{
return this.radius * this._PI
}
}
class program
{
public static void main()
{
Circle c1 = new Cirle();
flo...
Using Enum values as String literals
...of enums:
public final class Modes {
public static final String MODE_1 = "Fancy Mode 1";
public static final String MODE_2 = "Fancy Mode 2";
public static final String MODE_3 = "Fancy Mode 3";
private Modes() { }
}
Option Four: interfaces have every field public, static and fin...
HTML input - name vs. id [duplicate]
...letter
Must not contain anything other than letters, numbers, underscores (_), dashes (-), colons (:), or periods (.)
Is case insensitive
In (X)HTML5, everything is the same except:
Name Attribute
Not valid on <form> anymore
XHTML says it must be all lowercase, but most browsers don't fol...