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How to use clock() in C++
How do I call clock() in C++ ?
7 Answers
7
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Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...an work around it from within psql by executing the DDL statement conditionally:
SELECT 'CREATE DATABASE mydb'
WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec
The manual:
\gexec
Sends the current query buffer to the server, then treats each column of each row of the query's...
How do I get current date/time on the Windows command line in a suitable format for usage in a file/
Update: Now that it's 2016 I'd use PowerShell for this unless there's a really compelling backwards-compatible reason for it, particularly because of the regional settings issue with using date . See @npocmaka's https://stackoverflow.com/a/19799236/8479
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How to sort a list in Scala by two fields?
... @SachinK: You could implement customOrdering as Ordering[Row] manually or using Ordering.by like this: val customOrdering = Ordering.by((r: Row) => (r.lastName, r.firstName))( Ordering.Tuple2(Ordering.String.reverse, Ordering.String) )`
– senia
Jun ...
Adding :default => true to boolean in existing Rails column
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change_column is a method of ActiveRecord::Migration, so you can't call it like that in the console.
If you want to add a default value for this column, create a new migration:
rails g migration add_default_value_to_show_attribute
Then in the migration created:
# That's the more generic way t...
What do the python file extensions, .pyc .pyd .pyo stand for?
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.py: This is normally the input source code that you've written.
.pyc: This is the compiled bytecode. If you import a module, python will build a *.pyc file that contains the bytecode to make importing it again later easier (and faster).
.pyo...
Does IMDB provide an API? [closed]
...lo.json (alternate)
Format: JSON-P
Caveat: It's in JSON-P format, and the callback parameter can not customised. To use it cross-domain you'll have to use the function name they choose (which is in the imdb${searchphrase} format). Alternatively, one could strip or replace the padding via a local pro...
[科普] __MACOSX是什么文件夹？ - 更多技术 - 清泛网 - 专注C/C++及内核技术
[科普] __MACOSX是什么文件夹？（如图，一般的设计源文件都会有__MACOSX这个目录）以下为网上搜到的资料：MacOS作为他们的开发环境。例如，许多来自领先的网络框架组织的...
（如图，一般的设计源文件都会有__MACOSX这个目录）
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How to deep copy a list?
... don't make a deep copy using list() (Both list(...) and testList[:] are shallow copies).
You use copy.deepcopy(...) for deep copying a list.
deepcopy(x, memo=None, _nil=[])
Deep copy operation on arbitrary Python objects.
See the following snippet -
>>> a = [[1, 2, 3], [4, 5, 6]]...
iPhone get SSID without private library
...e(CNCopySupportedInterfaces());
NSLog(@"%s: Supported interfaces: %@", __func__, interfaceNames);
NSDictionary *SSIDInfo;
for (NSString *interfaceName in interfaceNames) {
SSIDInfo = CFBridgingRelease(
CNCopyCurrentNetworkInfo((__bridge CFStringRef)interfaceName));
...