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How to sort an array in descending order in Ruby
... 0.001631 0.110628 ( 0.111532)
...the reverse method doesn't actually return a reversed array - it returns an enumerator that just starts at the end and works backwards.
The source for Array#reverse is:
static VALUE
rb_ary_reverse_m(VALUE ary)
{
long len = RARRAY_LEN(...
Understanding __get__ and __set__ and Python descriptors
...th the Temperature class). For example:
temp=Temperature()
temp.celsius #calls celsius.__get__
Accessing the property you assigned the descriptor to (celsius in the above example) calls the appropriate descriptor method.
instance in __get__ is the instance of the class (so above, __get__ would r...
Create nice column output in python
...
This will make all columns the same width, which is not what column -t does.
– intuited
Dec 5 '12 at 0:54
...
How to delete or add column in SQLITE?
...upports a limited subset of ALTER TABLE. The ALTER TABLE command in SQLite allows the user to rename a table or to add a new column to an existing table. It is not possible to rename a column, remove a column, or add or remove constraints from a table.
You can:
create new table as the one you ar...
Get selected subcommand with argparse
...ser.add_subparsers(dest="subparser_name") # this line changed
>>> foo_parser = subparsers.add_parser('foo')
>>> foo_parser.add_argument('-c', '--count')
>>> bar_parser = subparsers.add_parser('bar')
>>> args = parser.parse_args(['-g', 'xyz', 'foo', '--count', '42'...
Best way to test for a variable's existence in PHP; isset() is clearly broken
... This looks a bit ugly to me, but in the case where you're actually checking an array element, it makes much more sense: isset($foo[$bar]) becomes array_key_exists($bar, $foo)
– Arild
Aug 25 '14 at 14:12
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Is arr.__len__() the preferred way to get the length of an array in Python?
...ples:
my_tuple = (1,2,3,4,5)
len(my_tuple)
# 5
And strings, which are really just arrays of characters:
my_string = 'hello world'
len(my_string)
# 11
It was intentionally done this way so that lists, tuples and other container types or iterables didn't all need to explicitly implement a public...
Is there a way of having git show lines added, lines changed and lines removed?
...
If all of your files are staged for commit, to see the --numstat go like this:
git diff --numstat HEAD~
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How to paste yanked text into the Vim command line
...you know how to use them you cannot live without them.
Registers are basically storage locations for strings. Vim has many registers that work in different ways:
0 (yank register: when you use y in normal mode, without specifying a register, yanked text goes there and also to the default register...
How to set child process' environment variable in Makefile
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I have GNU make 3.81, and all: <\n\t>export PROJ_ROOT=$(CURDIR)<\n\t>echo $(PROJ_ROOT)<\n> outputs the correct expansion for the first row, but only echo for the second one. PROJ_ROOT is not set after running make. Spaces around = gi...