大约有 40,000 项符合查询结果（耗时：0.0483秒） [XML]
How to get the first column of a pandas DataFrame as a Series?
...c wasn't there yet back then. In 2016, the correct answer is Jeff's (after all he's pandas God, mind you ;-)). I'm not sure what's SO's policy regarding update of answers due to API change; I'm honestly surprised by the number of votes for this answer, didn't think it was that useful to people...
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How to efficiently count the number of keys/properties of an object in JavaScript?
...t only iterates through the object but also creates a whole new array with all its keys, so it completely fails at answering the question.
– GetFree
Jun 22 '12 at 14:28
43
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Setting PATH environment variable in OSX permanently
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This worked in EL Capitan. Close all the terminals and open a new terminal to check echo $PATH.
– Prem Ananth C
Apr 3 '16 at 12:25
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JavaScript hashmap equivalent
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Hash your objects yourself manually, and use the resulting strings as keys for a regular JavaScript dictionary. After all, you are in the best position to know what makes your objects unique. That's what I do.
Example:
var key = function(obj){
// Some un...
How to printf uint64_t? Fails with: “spurious trailing ‘%’ in format”
...t. However the C++ committee chose to ignore the suggestion: e.g. in the n3242 draft, 27.9.2/3: Note: The macros defined by <cinttypes> are provided unconditionally. In particular, the symbol __STDC_FORMAT_MACROS, mentioned in footnote 182 of the C standard, plays no role in C++. So when the...
Is there a way to iterate over a range of integers?
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I don't think most people would call this three-expression version more simple than what @Vishnu wrote. Only perhaps after years and years of C or Java indoctrination ;-)
– Thomas Ahle
Jun 28 '14 at 21:06
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Visual Studio window which shows list of methods
...io, is there a window which shows list of methods in the active class? A small window like the Solution Explorer would be great. In Eclipse, there is one.
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How to pip or easy_install tkinter on Windows
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Well I can see two solutions here:
1) Follow the Docs-Tkinter install for Python (for Windows):
Tkinter (and, since Python 3.1, ttk) are included with all standard Python distributions. It is important that you use a version of Python supporting Tk 8.5 or greater, and ttk. We recommend in...
How to declare string constants in JavaScript? [duplicate]
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There's no constants in JavaScript, but to declare a literal all you have to do is:
var myString = "Hello World";
I'm not sure what you mean by store them in a resource file; that's not a JavaScript concept.
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General guidelines to avoid memory leaks in C++ [closed]
... programs? How do I figure out who should free memory that has been dynamically allocated?
29 Answers
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