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Quickest way to convert a base 10 number to any base in .NET?
... digits = (new[] { NullDigit }).Concat(digits);
}
_digitToIndexMap =
digits
.Select((digit, index) => new { digit, index })
.ToDictionary(keySelector: x => x.digit, elementSelector: x => x.index);
_radix =...
Importing a CSV file into a sqlite3 database table using Python
...csv, sqlite3
con = sqlite3.connect(":memory:") # change to 'sqlite:///your_filename.db'
cur = con.cursor()
cur.execute("CREATE TABLE t (col1, col2);") # use your column names here
with open('data.csv','r') as fin: # `with` statement available in 2.5+
# csv.DictReader uses first line in file fo...
What are dictionary view objects?
...
>>> del dishes['eggs']
>>> keys # No eggs anymore!
dict_keys(['sausage', 'bacon', 'spam'])
>>> values # No eggs value (2) anymore!
dict_values([1, 1, 500])
(The Python 2 equivalent uses dishes.viewkeys() and dishes.viewvalues().)
This example shows the dynamic char...
Virtual Memory Usage from Java under Linux, too much memory used
...6-x64/jre/lib/amd64/libjava.so
...
00007fa1f34aa000 1576K r-x-- /lib/x86_64-linux-gnu/libc-2.13.so
00007fa1f3634000 2044K ----- /lib/x86_64-linux-gnu/libc-2.13.so
00007fa1f3833000 16K r-x-- /lib/x86_64-linux-gnu/libc-2.13.so
00007fa1f3837000 4K rwx-- /lib/x86_64-linux-gnu/libc-2.13....
How to print a percentage value in python?
...If you don't want integer division, you can import Python3's division from __future__:
>>> from __future__ import division
>>> 1 / 3
0.3333333333333333
# The above 33% example would could now be written without the explicit
# float conversion:
>>> print "{0:.0f}%".format...
How to convert An NSInteger to an int?
...endently of whether you are building for a 32-bit or a 64-bit system.
#if __LP64__ || TARGET_OS_EMBEDDED || TARGET_OS_IPHONE || TARGET_OS_WIN32 || NS_BUILD_32_LIKE_64
typedef long NSInteger;
#else
typedef int NSInteger;
#endif
You can use NSInteger any place you use an int without converting it....
Get a random boolean in python?
...----------------------------------------------------------------
def create_values(fake):
""""""
print fake.boolean(chance_of_getting_true=50) # True
print fake.random_int(min=0, max=1) # 1
if __name__ == "__main__":
fake = Factory.create()
create_values(fake)
...
What is the difference between Python's list methods append and extend?
...ppend
The list.append method appends an object to the end of the list.
my_list.append(object)
Whatever the object is, whether a number, a string, another list, or something else, it gets added onto the end of my_list as a single entry on the list.
>>> my_list
['foo', 'bar']
>>&...
Rank function in MySQL
...ption is to use a ranking variable, such as the following:
SELECT first_name,
age,
gender,
@curRank := @curRank + 1 AS rank
FROM person p, (SELECT @curRank := 0) r
ORDER BY age;
The (SELECT @curRank := 0) part allows the variable initialization without requi...
How to get Scala List from Java List?
...now built into the language using:
import scala.collection.JavaConversions._
...
lst.toList.foreach{ node => .... }
works. asScala did not work
In 2.12.x use import scala.collection.JavaConverters._
In 2.13.x use import scala.jdk.CollectionConverters._
...