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Why should eval be avoided in Bash, and what should I use instead?
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Create a dictionary with list comprehension
...y: value for (key, value) in iterable}
Note: this is for Python 3.x (and 2.7 upwards). Formerly in Python 2.6 and earlier, the dict built-in could receive an iterable of key/value pairs, so you can pass it a list comprehension or generator expression. For example:
dict((key, func(key)) for key in ...
Using awk to print all columns from the nth to the last
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Remove an entire column from a data.frame in R
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421
You can set it to NULL.
> Data$genome <- NULL
> head(Data)
chr region
1 chr1 CD...
Check if something is (not) in a list in Python
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Multiple linear regression in Python
...ress my dependent variable (y) against several independent variables (x1, x2, x3, etc.).
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How to write log base(2) in c/c++
Is there any way to write log(base 2) function?
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App Inventor 2 能否实现后台推送通知？源码级深度调研 - App应用开发 - 清...
背景：微信群用户提问
AI2 能否实现类似 uni-push 的后台推送通知？手机开机不打开 App 就能自动读取云端数据。
以下是源码级深度调研结果。
一、推送通知的工作原理
系统级推送（真推送）
服务器 -> FCM/APNs 云...
Python dictionary: Get list of values for list of keys
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A list comprehension seems to be a good way to do this:
>>> [mydict[x] for x in myke...
How to silence output in a Bash script?
...ou'll want to silence that. You can do that by redirecting file descriptor 2:
# Send stdout to out.log, stderr to err.log
myprogram > out.log 2> err.log
# Send both stdout and stderr to out.log
myprogram &> out.log # New bash syntax
myprogram > out.log 2>&1 # Older sh ...