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Creating an R dataframe row-by-row
...d like to construct a dataframe row-by-row in R. I've done some searching, and all I came up with is the suggestion to create an empty list, keep a list index scalar, then each time add to the list a single-row dataframe and advance the list index by one. Finally, do.call(rbind,) on the list.
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MIN and MAX in C
Where are MIN and MAX defined in C, if at all?
14 Answers
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Quickly reading very large tables as dataframes
...ahead of time, the table does not contain any column headers or row names, and does not have any pathological characters that I have to worry about.
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How to break out of multiple loops?
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My first instinct would be to refactor the nested loop into a function and use return to break out.
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Why should hash functions use a prime number modulus?
...g the "component parts" of the input (characters in the case of a string), and multiplying them by the powers of some constant, and adding them together in some integer type. So for example a typical (although not especially good) hash of a string might be:
(first char) + k * (second char) + k^2 * ...
shared_ptr to an array : should it be used?
...r delete p, when T is not an array type, shall have well-defined behavior, and shall not throw exceptions.
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Remarks: When T is an array type, this constructor shall not participate in overload resolution unless the expression delete[] p is well-formed and either T is U[N] and Y(*)[N] is conve...
C++常用排序算法汇总 - C/C++ - 清泛网 - 专注C/C++及内核技术
...QuickSort)，归并排序(MergeSort)，堆排序(HeapSort)，插入排序(InsertSort)，希尔排序(ShellSort) 1、选择排序(SelectSort)
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* 简单选择排序
* 稳定排序，O{n^2} ~ O{n^2}
* 从首位开始，循环一次找出一个比首位小...
Stop and Start a service via batch or cmd file?
How can I script a bat or cmd to stop and start a service reliably with error checking (or let me know that it wasn't successful for whatever reason)?
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How to count instances of character in SQL Column
...t 0. Easiest way would be to add a trailing character to the string before and adjust len like so. SELECT LEN(col + '~') - LEN(REPLACE(col, 'Y', '') + '~')
– domenicr
Sep 23 '15 at 18:10
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multiple prints on the same line in Python
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This doesn't work if you have both prints and a time consuming action in between (all in the same function / indentation level). Before the action starts, there is no output at all and after it is finished the output appears as whole
– Paddre
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