大约有 6,888 项符合查询结果(耗时:0.0211秒) [XML]

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GroupBy pandas DataFrame and select most common value

...,'NY']}) source.groupby(['Country','City']).agg(lambda x:x.value_counts().index[0]) In case you are wondering about performing other agg functions in the .agg() try this. # Let's add a new col, account source['account'] = [1,2,3,3] source.groupby(['Country','City']).agg(mod = ('Short name', \...
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Getting JavaScript object key list

... you need to increment array index – Vivek Jul 14 '14 at 9:43 array inde...
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vector::at vs. vector::operator[]

...bugs in your code. If you need to bounds-check at runtime because e.g. the index comes from user input, you're indeed best off with an if statement. So in summary, design your code with the intention that vector::at() will never throw an exception, so that if it does, and your program aborts, it's a...
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How can I set the value of a DropDownList using jQuery?

... If you working with index you can set the selected index directly with .attr(): $("#mydropdownlist").attr('selectedIndex', 0); This will set it to the first value in the droplist. Edit: The way I did it above used to work. But it seems like ...
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Replace all spaces in a string with '+' [duplicate]

...ll(Source, stringToFind, stringToReplace) { var temp = Source; var index = temp.indexOf(stringToFind); while (index != -1) { temp = temp.replace(stringToFind, stringToReplace); index = temp.indexOf(stringToFind); } return temp; } String.prototype.ReplaceAll = f...
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Creating a new column based on if-elif-else condition

...B'], 'C'] = 1 df.loc[df['A'] < df['B'], 'C'] = -1 Easy to solve using indexing. The first line of code reads like so, if column A is equal to column B then create and set column C equal to 0. share | ...
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Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?

...p being the effective maximum if you want to use UTF-8 and have the column indexed (because of index length limitations). share | improve this answer | follow ...
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How can I get a java.io.InputStream from a java.lang.String?

... private final Writer encoder; private final String data; private int index; public StringInputStream(String sequence, Charset charset) { data = sequence; encoder = new OutputStreamWriter( new OutputStreamBuffer(), charset); } private int buffer() throws IOException { ...
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Algorithm to return all combinations of k elements from n

...hm 382: Combinations of M out of N Objects' (1970) The algorithm in C... Index of Combinations in Lexicographical Order (Buckles Algorithm 515) You can also reference a combination by its index (in lexicographical order). Realizing that the index should be some amount of change from right to lef...
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Using DNS to redirect to another URL with a path [closed]

... subdomains, so instead of: www.proof.com IN CNAME www.proof-two.com/path/index.htm You could use: www.proof.com IN CNAME proof.proof-two.com then go to wherever you host proof-two.com and set it to point proof.proof-two.com to www.proof-two.com/path/index.htm. ~ there's always more than one wa...