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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 =...
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...
How to convert a string to utf-8 in Python
...
In Python 2
>>> plain_string = "Hi!"
>>> unicode_string = u"Hi!"
>>> type(plain_string), type(unicode_string)
(<type 'str'>, <type 'unicode'>)
^ This is the difference between a byte string (plain_string) and a unic...
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']
>>&...
How to call C from Swift?
... frame = CGRect(x: 10, y: 10, width: 100, height: 100)
import Darwin
for _ in 1..10 {
println(rand() % 100)
}
See Interacting with Objective-C APIs in the docs.
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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....
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...
Return a value if no rows are found in Microsoft tSQL
... but ideally it should return multiple values. select case when count(QTIB_REQ_)<1 then 0 else QTIB_REQ_ end from qb_requisitions_all where QTIB_REQ_ IN ($Req_disabled_WA) and CLIENT___BENCH___NON_BILLABLE NOT IN ( 'Non Billable', 'Non-Billable', 'NonBillable', 'Bench', 'Bench - SC Cleared S...
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._
...