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What's the @ in front of a string in C#?
...tring as a verbatim string literal - anything in the string that would normally be interpreted as an escape sequence is ignored.
So "C:\\Users\\Rich" is the same as @"C:\Users\Rich"
There is one exception: an escape sequence is needed for the double quote. To escape a double quote, you need to put...
python dataframe pandas drop column using int
... columns with identical names, the solutions given here so far will remove all of the columns, which may not be what one is looking for. This may be the case if one is trying to remove duplicate columns except one instance. The example below clarifies this situation:
# make a df with duplicate col...
Django: Get model from string?
...d in 1.9) in favor of the the new application loading system.
-- Scott Woodall
Found it. It's defined here:
from django.db.models.loading import get_model
Defined as:
def get_model(self, app_label, model_name, seed_cache=True):
...
What are the differences between concepts and template constraints?
...To quickly summarise their meanings:
Constraint - A predicate over statically evaluable properties of a type. Purely syntactic requirements. Not a domain abstraction.
Axioms - Semantic requirements of types that are assumed to be true. Not statically checked.
Concepts - General, abstract requireme...
What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
6 Answers
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python max function using 'key' and lambda expression
... def. Thus, you can't use statements inside a lambda, only expressions are allowed.
What does max do?
max(a, b, c, ...[, key=func]) -> value
With a single iterable argument, return its largest item. With two or
more arguments, return the largest argument.
So, it simply returns the...
Coalesce function for PHP?
...HP 7 introduced a real coalesce operator:
echo $_GET['doesNotExist'] ?? 'fallback'; // prints 'fallback'
If the value before the ?? does not exists or is null the value after the ?? is taken.
The improvement over the mentioned ?: operator is, that the ?? also handles undefined variables without...
Android ACTION_IMAGE_CAPTURE Intent
...works just fine if we leave out the EXTRA_OUTPUT extra and returns the small Bitmap image. However, if we putExtra(EXTRA_OUTPUT,...) on the intent before starting it, everything works until you try to hit the "Ok" button in the camera app. The "Ok" button just does nothing. The camera app stays ...
image processing to improve tesseract OCR accuracy
... highly pixellated - for example that generated by fax machines - is especially difficult for tesseract to process - presumably all those jagged edges to the characters confound the shape-recognition algorithms.
...
What is the reason why “synchronized” is not allowed in Java 8 interface methods?
...t seem sensible to extend this semantics to default methods as well; after all, they are instance methods with a receiver too. (Note that synchronized methods are entirely a syntactic optimization; they're not needed, they're just more compact than the corresponding synchronized block. There's a r...