大约有 30,000 项符合查询结果（耗时：0.0533秒） [XML]
What are the “standard unambiguous date” formats for string-to-date conversion in R?
...
This is documented behavior. From ?as.Date:
format: A character string. If not specified, it will try
'"%Y-%m-%d"' then '"%Y/%m/%d"' on the first non-'NA' element,
and give an error if neither works.
as.Date("01 Jan 2000") yields an error because the format isn'...
How to get innerHTML of DOMNode?
...hiteSpace = false;
$dom->formatOutput = true;
$dom->load($html_string);
$domTables = $dom->getElementsByTagName("table");
// Iterate over DOMNodeList (Implements Traversable)
foreach ($domTables as $table)
{
echo DOMinnerHTML($table);
}
?>
...
Is there a builtin identity function in python?
... thanks, I have a trivial lambda x: x identity function that works for one string parameter. @Marcin I wish I could do lambda *args: *args :-)
– rds
Jan 6 '12 at 0:01
...
Read-only list or unmodifiable list in .NET 4.0
...oking for ReadOnlyCollection, which has been around since .NET2.
IList<string> foo = ...;
// ...
ReadOnlyCollection<string> bar = new ReadOnlyCollection<string>(foo);
or
List<string> foo = ...;
// ...
ReadOnlyCollection<string> bar = foo.AsReadOnly();
This creates...
Read file data without saving it in Flask
...d file.stream.read(). Also you can use save argument with dst parameter as StringIO or other IO or file object to copy FileStorage.stream to another IO or file object.
See documentation: http://flask.pocoo.org/docs/api/#flask.Request.files and http://werkzeug.pocoo.org/docs/datastructures/#werkzeug...
Debug code-first Entity Framework migration codes
...y, the trick is to grab all the information from an exception, put it in a string and throw a new DbEntityValidationException with the generated string and the original exception.
share
|
improve th...
Python regular expressions return true/false
...
re.match(...) would return true if the string's beginning part match the regular pattern. While search will confirm the pattern anywhere in the string.
– Yu Shen
Jun 8 '13 at 9:57
...
Pandas aggregate count distinct
...
Just adding to the answers already given, the solution using the string "nunique" seems much faster, tested here on ~21M rows dataframe, then grouped to ~2M
%time _=g.agg({"id": lambda x: x.nunique()})
CPU times: user 3min 3s, sys: 2.94 s, total: 3min 6s
Wall time: 3min 20s
%time _=g.ag...
What is the correct JSON content type?
...
{
@Override
public void onActionFailed(Form form, int httpStatus, String responseText)
{
MessageBox.alert("Error");
}
@Override
public void onActionComplete(Form form, int httpStatus, String responseText)
{
MessageBox.alert("Success");
}
});
In c...
Java regex capturing groups indexes
...oup numbers are used in back-reference \n in pattern and $n in replacement string.
In other regex flavors (PCRE, Perl), they can also be used in sub-routine calls.
You can access the text matched by certain group with Matcher.group(int group). The group numbers can be identified with the rule stat...