大约有 40,000 项符合查询结果(耗时:0.0608秒) [XML]

https://stackoverflow.com/ques... 

Converting a column within pandas dataframe from int to string

... I really don't understand why, but mtrx['X.3'].apply(str) does not work for me either :( dtype still shows int64. The dataframe for 23177 row and X.3 column got only numbers. In [21]: mtrx['X.3'].dtype Out[21]: dtype('i...
https://stackoverflow.com/ques... 

How do I install an old version of Django on virtualenv?

...d question, since the very purpose of virtualenv is to this exactly: Installing some specific version of a package (in this case Django) inside the virtual environment. But it's exactly what I want to do, and I can't figure it out. ...
https://stackoverflow.com/ques... 

When should std::move be used on a function return value? [duplicate]

... to the return value of meh is required to be the move constructor if one exists. Adding move does have a potential effect, though: it prevents the move being elided, because return std::move(foo); is not eligible for NRVO. As far as I know, 12.8/32 lays out the only conditions under which a copy ...
https://stackoverflow.com/ques... 

How to specify data attributes in razor, e.g., data-externalid=“23151” on @this.Html.CheckBoxFor(…)

...heckBox", data_externalid = "23521" } ) The _ will automatically be converted to - in the resulting markup: <input type="checkbox" name="MyModel.MyBoolProperty" data-externalid="23521" class="myCheckBox" /> And that's true for all Html helpers taking a htmlAttributes anonymou...
https://stackoverflow.com/ques... 

Python list sort in descending order

... In one line, using a lambda: timestamp.sort(key=lambda x: time.strptime(x, '%Y-%m-%d %H:%M:%S')[0:6], reverse=True) Passing a function to list.sort: def foo(x): return time.strptime(x, '%Y-%m-%d %H:%M:%S')[0:6] timestamp.sort(key=foo, reverse=True) ...
https://stackoverflow.com/ques... 

Getting the parent div of element

This should be really simple but I'm having trouble with it. How do I get a parent div of a child element? 7 Answers ...
https://stackoverflow.com/ques... 

How do I compile C++ with Clang?

... Also, for posterity -- Clang (like GCC) accepts the -x switch to set the language of the input files, for example, $ clang -x c++ some_random_file.txt This mailing list thread explains the difference between clang and clang++ well: Difference between clang and clang++ ...
https://stackoverflow.com/ques... 

How do I delete rows in a data frame?

...by the '-' operator" -> This is a very misleading wording. Negative indexes are removed and that's it, there is no notion of complement. If you work with logical and try using - it won't work, because the complement operator for logicals is !. The complement of c(2,4,6) in the rows would rather b...
https://stackoverflow.com/ques... 

How do I hide a menu item in the actionbar?

... Get a MenuItem pointing to such item, call setVisible on it to adjust its visibility and then call invalidateOptionsMenu() on your activity so the ActionBar menu is adjusted accordingly. Update: A MenuItem is not a regular view that's part of your layout. Its som...
https://stackoverflow.com/ques... 

How to pad zeroes to a string?

...ited in the parens; since only one thing is being printed, it works identically now on Py2 and Py3. – ShadowRanger Jan 25 '19 at 2:19 2 ...