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Drawing an image from a data URL to a canvas
...n a data URL, you can create an image (either on the page or purely in JS) by setting the src of the image to your data URL. For example:
var img = new Image;
img.src = strDataURI;
The drawImage() method of HTML5 Canvas Context lets you copy all or a portion of an image (or canvas, or video) onto...
How to sum a variable by group
...
Using aggregate:
aggregate(x$Frequency, by=list(Category=x$Category), FUN=sum)
Category x
1 First 30
2 Second 5
3 Third 34
In the example above, multiple dimensions can be specified in the list. Multiple aggregated metrics of the same data type can ...
Objective-C pass block as parameter
...jective-C code, how can I tell if a block is escaping or not? I read that by default, blocks are escaping except if decorated with NS_NOESCAPE, but enumerateObjectsUsingBlock I'm told is non-escaping, yet I don't see NS_NOESCAPE anywhere in site, nor is escaping mentioned at all in the Apple docs. ...
Why use multiple columns as primary keys (composite primary key)
...ble as for other keys.
Their choice of example is perhaps misleading you by combining a meaningless key (P_Id) and a natural key (LastName). This odd choice of primary key says that the following rows are valid according to the schema and are necessary to uniquely identify a student. Intuitively t...
Does a UNIQUE constraint automatically create an INDEX on the field(s)?
... imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454...
Open Facebook page from Android app?
...t, and is very easy.
I discovered this after looking into how emails send by facebook opened the app.
// e.g. if your URL is https://www.facebook.com/EXAMPLE_PAGE, you should put EXAMPLE_PAGE at the end of this URL, after the ?
String YourPageURL = "https://www.facebook.com/n/?YOUR_PAGE_NAME";
Int...
Android: Scale a Drawable or background image?
...
none of these parameters scales bitmap, by keeping it's aspect ration, so the answer is wrong.
– Malachiasz
Jan 31 '14 at 14:04
7
...
How do I create a slug in Django?
...ify("b b b b")
u'b-b-b-b'
>>>
You can call slugify automatically by overriding the save method:
class Test(models.Model):
q = models.CharField(max_length=30)
s = models.SlugField()
def save(self, *args, **kwargs):
self.s = slugify(self.q)
super(Test, self)....
How to convert “camelCase” to “Camel Case”?
...-Z])/g, '$1 $2')
// space before last upper in a sequence followed by lower
.replace(/\b([A-Z]+)([A-Z])([a-z])/, '$1 $2$3')
// uppercase the first character
.replace(/^./, function(str){ return str.toUpperCase(); })
}
There's also a String.prototype version in a gis...
Shiro vs. SpringSecurity [closed]
...pring Security? Neither are as simple and intuitive as Shiro's solution:
ByteSource salt = new SecureRandomNumberGenerator().nextBytes();
new Sha512Hash(password, salt).toBase64();
No need for commons-codec or anything else. Just the Shiro jar.
Now with regards to Spring environments, most of ...