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What is the result of % in Python?
...erator, so watch out if you are coming from a language with automatic type casting (like PHP or JS) where an expression like '12' % 2 + 3 is legal: in Python it will result in TypeError: not all arguments converted during string formatting which probably will be pretty confusing for you.
[update for...
Macro vs Function in C
...ch as checking their type, sizeof, check struct members are present before casting(can be useful for polymorphic types).Or check an array meets some length condition.see: https://stackoverflow.com/a/29926435/432509
While its noted that functions do type checking, C will coerce values too (ints/float...
MySQL Results as comma separated list
...in and want to output a comma-delimited list to the page, use GROUP_CONCAT(CAST(s.name AS CHAR)) or else it will just return something wholly unuseful like [BLOB - 20 Bytes].
– devios1
Mar 1 '12 at 15:52
...
How to split a column into two columns?
...s is (NaN) which will result in ValueError (to overcome this issue you can cast it to string type before splitting). I recommend you to try it on your own it's the best way of learning :-)
– Nerxis
Dec 18 '19 at 8:07
...
get list from pandas dataframe column
...then call x.tolist() on to turn them into a Python list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], index=['a', 'b', 'c', 'd'])}
df = pd.DataFrame(data_dict)
print(f"DataF...
Using current time in UTC as default value in PostgreSQL
...now()::timestamp
If your other timestamp are without time zone then this cast will yield the matching type "timestamp without time zone" for the current time.
I would like to read what others think about that option, though. I still don't trust in my understanding of this "with/without" time zone...
Should the hash code of null always be zero, in .NET
...riteLine((int)v);
it return 0, as expected, or simple Spring if we avoid casting to int.
So.. if you do the following:
Season? v = Season.Spring;
Season? vnull = null;
if(vnull == v) // never TRUE
EDIT
From MSDN
If two objects compare as equal, the GetHashCode method for each object m...
C++ static virtual members?
...ely type-safe and doesn't contain any black magic like typeid's or dynamic_cast's :)
So, we want to provide only one definition of getTypeInformation() per derived class and it is obvious that it has to be a definition of static function because it is not possible to call "SomeDerivedClass::getType...
Handling warning for possible multiple enumeration of IEnumerable
...ToReadOnly<T>(this IList<T> list) extension method that simple casts if the underlying type supports both interfaces, but you have to add it manually everywhere when refactoring, where as IEnumerable<T> is always compatible.)
As always this is not an absolute, if you're writing da...
Generating random integer from a range
... properly uniform distributed solution is
output = min + (rand() % static_cast<int>(max - min + 1))
Except when the size of the range is a power of 2, this method produces biased non-uniform distributed numbers regardless the quality of rand(). For a comprehensive test of the quality of thi...