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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...
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...
How to suppress Update Links warning?
...
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 ...
Appending an element to the end of a list in Scala
...
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).
...
Is there an easy way to create ordinals in C#?
...
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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?
...
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...
How do you express binary literals in Python?
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298
For reference—future Python possibilities:
Starting with Python 2.6 you can express binary l...
Request failed: unacceptable content-type: text/html using AFNetworking 2.0
I'm trying out the new version 2.0 of AFNetworking and I'm getting the error above. Any idea why this is happening? Here's my code:
...
App Inventor 2 Encrypt.Security 安全性扩展：MD5哈希，SHA1和SHA256哈希...
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App Inventor 2 Encrypt.Security 安全性扩...