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Specify format for input arguments argparse python
... can take any callable that takes a single string argument and returns the converted value
You could do something like:
def valid_date(s):
try:
return datetime.strptime(s, "%Y-%m-%d")
except ValueError:
msg = "Not a valid date: '{0}'.".format(s)
raise argparse.Argu...
Difference between Char.IsDigit() and Char.IsNumber() in C#
What's the difference between Char.IsDigit() and Char.IsNumber() in C#?
3 Answers
...
What is the convention for word separator in Java package names?
...ins a hyphen, or any other special character not allowed in an identifier, convert it into an underscore.
If any of the resulting package name components are keywords then append underscore to them.
If any of the resulting package name components start with a digit, or any other character that i...
Array initializing in Scala
...ed here: stackoverflow.com/questions/13862568/…)
– Anderson Green
Jun 14 '13 at 22:50
add a...
Label encoding across multiple columns in scikit-learn
...
We don't need a LabelEncoder.
You can convert the columns to categoricals and then get their codes. I used a dictionary comprehension below to apply this process to every column and wrap the result back into a dataframe of the same shape with identical indices a...
Split value from one field to two
I've got a table field membername which contains both the last name and the first name of users. Is it possible to split those into 2 fields memberfirst , memberlast ?
...
Reading a delimited string into an array in Bash
...
In order to convert a string into an array, please use
arr=($line)
or
read -a arr <<< $line
It is crucial not to use quotes since this does the trick.
...
psycopg2: insert multiple rows with one query
...e which allows an iterator yielding strings to be read like a file. We can convert each input record to a string using a generator expression. So the solution would be
args = [(1,2), (3,4), (5,6)]
f = IteratorFile(("{}\t{}".format(x[0], x[1]) for x in args))
cursor.copy_from(f, 'table_name', column...
Is there a regular expression to detect a valid regular expression?
...n directly. (The (?1) and (?R) constructs.) The recursion would have to be converted to counting balanced groups:
^ # start of string
(?:
(?: [^?+*{}()[\]\\|]+ # literals and ^, $
| \\. # escaped charact...
How to add column if not exists on PostgreSQL?
...
Here's a short-and-sweet version using the "DO" statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THE...