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Adding a column to a data.frame
I have the data.frame below. I want to add a column that classifies my data according to column 1 ( h_no ) in that way that the first series of h_no 1,2,3,4 is class 1, the second series of h_no (1 to 7) is class 2 etc. such as indicated in the last column.
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How to avoid explicit 'self' in Python?
I have been learning Python by following some pygame tutorials .
11 Answers
11
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Why does PHP 5.2+ disallow abstract static class methods?
After enabling strict warnings in PHP 5.2, I saw a load of strict standards warnings from a project that was originally written without strict warnings:
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assign multiple variables to the same value in Javascript
I have initialized several variables in the global scope in a JavaScript file:
5 Answers
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Creating a “logical exclusive or” operator in Java
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Java does have a logical XOR operator, it is ^ (as in a ^ b).
Apart from that, you can't define new operators in Java.
Edit: Here's an example:
public static void main(String[] args) {
boolean[] all = { false, true };
for (boolean a : all) {
for (boolean b: all) ...
How to count the frequency of the elements in an unordered list?
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Note: You should sort the list before using groupby.
You can use groupby from itertools package if the list is an ordered list.
a = [1,1,1,1,2,2,2,2,3,3,4,5,5]
from itertools import groupby
[len(list(group)) for key, group in groupby(a)]
Output:
[4, 4...
Android微信智能心跳方案 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...心跳就可以很大程度的保证下一次心跳环境是正常的。
b）成功一次认定，失败连续累积认定：成功是绝对的，连续失败多次才可能是失败。
c）临界值避免：我们使用比计算出的心跳稍微小一点的值做为稳定心跳避免临界值。...
Assign pandas dataframe column dtypes
... I've had to manually parse into a list of lists, as the file was not amenable for pd.read_csv )
6 Answers
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Is there a difference between using a dict literal and a dict constructor?
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I think you have pointed out the most obvious difference. Apart from that,
the first doesn't need to lookup dict which should make it a tiny bit faster
the second looks up dict in locals() and then globals() and the finds the builtin, so you can switch the beh...
Remove an item from a dictionary when its key is unknown
What is the best way to remove an item from a dictionary by value, i.e. when the item's key is unknown? Here's a simple approach:
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