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Is there an R function for finding the index of an element in a vector?
...rks on vectors :
x <- sample(1:10)
x
# [1] 4 5 9 3 8 1 6 10 7 2
match(c(4,8),x)
# [1] 1 5
match only returns the first encounter of a match, as you requested. It returns the position in the second argument of the values in the first argument.
For multiple matching, %in% is the way to...
How to suppress Update Links warning?
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UPDATE:
After all the details summarized and discussed, I spent 2 fair hours in checking the options, and this update is to dot all is.
Preparations
First of all, I performed a clean Office 2010 x86 install on Clean Win7 SP1 Ultimate x64 virtual machine powered by VMWare (this is usual ...
Changing the “tick frequency” on x or y axis in matplotlib?
...rt numpy as np
import matplotlib.pyplot as plt
x = [0,5,9,10,15]
y = [0,1,2,3,4]
plt.plot(x,y)
plt.xticks(np.arange(min(x), max(x)+1, 1.0))
plt.show()
(np.arange was used rather than Python's range function just in case min(x) and max(x) are floats instead of ints.)
The plt.plot (or ax.plot...
Appending an element to the end of a list in Scala
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List(1,2,3) :+ 4
Results in List[Int] = List(1, 2, 3, 4)
Note that this operation has a complexity of O(n). If you need this operation frequently, or for long lists, consider using another data type (e.g. a ListBuffer).
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Convert columns to string in Pandas
...n (and therefore your keys to strings):
In [11]: df = pd.DataFrame([['A', 2], ['A', 4], ['B', 6]])
In [12]: df.to_json()
Out[12]: '{"0":{"0":"A","1":"A","2":"B"},"1":{"0":2,"1":4,"2":6}}'
In [13]: df[0].to_json()
Out[13]: '{"0":"A","1":"A","2":"B"}'
Note: you can pass in a buffer/file to save t...
Is there an easy way to create ordinals in C#?
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21 Answers
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FAT32系统中长文件名的存储 - C/C++ - 清泛网 - 专注C/C++及内核技术
FAT32系统中长文件名的存储FAT32的一个重要的特点是完全支持长文件名。长文件名依然是记录在目录项中的。为了低版本的OS或程序能正确读取长文件名文件，系统自动为所...FAT32的一个重要的特点是完全支持长文件名。长文件名...
How would I get a cron job to run every 30 minutes?
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edited Sep 27 '11 at 13:45
Tim Cooper
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Convert a list to a data frame
I have a nested list of data. Its length is 132 and each item is a list of length 20. Is there a quick way to convert this structure into a data frame that has 132 rows and 20 columns of data?
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Can't install Ruby under Lion with RVM – GCC issues
... questions regarding this problem are due to missing Xcode; I have Xcode 4.2 installed.
16 Answers
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