大约有 48,000 项符合查询结果（耗时：0.0272秒） [XML]
List comprehension in Ruby
..._ARRAY.map{|x| x % 2 == 0 ? x * 3 : nil}.compact
end
end
def test_select_map
1000.times do
TEST_ARRAY.select{|x| x % 2 == 0 }.map{|x| x * 3}
end
end
def test_inject
1000.times do
TEST_ARRAY.inject([]) {|all, x| all << x*3 if x % 2 == 0; all }
end
end...
Map and Reduce in .NET
...ons. C# 3.5 and Linq already has it albeit under different names.
Map is Select:
Enumerable.Range(1, 10).Select(x => x + 2);
Reduce is Aggregate:
Enumerable.Range(1, 10).Aggregate(0, (acc, x) => acc + x);
Filter is Where:
Enumerable.Range(1, 10).Where(x => x % 2 == 0);
https://www...
Export query result to .csv file in SQL Server 2008
...opy the query.
In Object Explorer right-click on the database in question.
Select "Tasks" >> "Export Data..."
Configure your datasource, and click "Next".
Choose "Flat File" or "Microsoft Excel" as destination.
Specify a file path.
If working with a flat file, configure as desired. If working ...
Python loop counter in a for loop [duplicate]
...
Use enumerate() like so:
def draw_menu(options, selected_index):
for counter, option in enumerate(options):
if counter == selected_index:
print " [*] %s" % option
else:
print " [ ] %s" % option
options = ['Option 0', 'Option...
adding and removing classes in angularJs using ng-click
...s code actuali change class for all div, how I can apply class only to the selected clicked item
– xzegga
Apr 24 '14 at 4:44
...
foreach with index [duplicate]
...
You can do the following
foreach (var it in someCollection.Select((x, i) => new { Value = x, Index = i }) )
{
if (it.Index > SomeNumber) //
}
This will create an anonymous type value for every entry in the collection. It will have two properties
Value: with the ori...
Android Gallery on Android 4.4 (KitKat) returns different URI for Intent.ACTION_GET_CONTENT
...tyForResult(Intent.createChooser(intent, getResources().getString(R.string.select_picture)),GALLERY_INTENT_CALLED);
} else {
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("image/jpeg");
startActivityForResult(int...
How to call Android contacts list?
...TION_PICK on the People.CONTENT_URI, then return to this Activity when the selection is made (or canceled).
startActivityForResult(intent, PICK_CONTACT);
3. Listening for the Result
Also in your Activity, override the onActivityResult method to listen for the return from the 'select a contact' A...
How can I change the file type association of an existing file in WebStorm?
...t patterns by which a file gets associated as some type or other.
If you select the patterns for a file type you have wrongly selected (in your case Text type) you can remove the filename pattern with which was created to associate you file's filename as a wrong type.
Then click Apply > OK
...
How do I find a default constraint using INFORMATION_SCHEMA?
...our constraints!)
-- returns name of a column's default value constraint
SELECT
default_constraints.name
FROM
sys.all_columns
INNER JOIN
sys.tables
ON all_columns.object_id = tables.object_id
INNER JOIN
sys.schemas
ON tables.schema_id = schemas.s...