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Multiple aggregations of the same column using pandas GroupBy.agg()
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You can simply pass the functions as a list:
In [20]: df.groupby("dummy").agg({"returns": [np.mean, np.sum]})
Out[20]:
mean sum
dummy
1 0.036901 0.369012
or as a dictionary:
In [21]: df.groupby('dummy').agg({'returns':
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How to use hex color values
...f, green ff and blue ff. You can write hexadecimal notation in Swift using 0x prefix, e.g 0xFF
To simplify the conversion, let's create an initializer that takes integer (0 - 255) values:
extension UIColor {
convenience init(red: Int, green: Int, blue: Int) {
assert(red >= 0 &&...
How to validate an e-mail address in swift?
...ValidEmail(_ email: String) -> Bool {
let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
let emailPred = NSPredicate(format:"SELF MATCHES %@", emailRegEx)
return emailPred.evaluate(with: email)
}
for versions of Swift earlier than 3.0:
func isValidEmail(e...
How do you convert epoch time in C#?
...ou convert Unix epoch time into real time in C#? (Epoch beginning 1/1/1970)
14 Answers
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Generate array of all letters and digits
...g ruby, is it possible to make an array of each letter in the alphabet and 0-9 easily?
7 Answers
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show all tags in git log
... namespace) is purely local matter; what one repository has in 'refs/tags/v0.1.3', other can have in 'refs/tags/sub/v0.1.3' for example.
So when you create signed tag 'A', you have the following situation (assuming that it points at some commit)
35805ce <--- 5b7b4ead <=== refs/t...
Combine two columns of text in pandas dataframe
I have a 20 x 4000 dataframe in Python using pandas. Two of these columns are named Year and quarter . I'd like to create a variable called period that makes Year = 2000 and quarter= q2 into 2000q2 .
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Angular.js ng-repeat across multiple tr's
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edited May 23 '17 at 12:10
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answered Oct 19 '12 at 20:19
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水果vs蔬菜智能分类器 - EdgeML图像识别项目 · App Inventor 2 中文网
...试）
环境要求
Android版本: 5.0 (API 21) 或更高
内存要求: 最低2GB RAM，推荐4GB以上
存储空间: 50MB以上（用于模型和应用）
摄像头权限: 用于实时图像捕获
存储权限: 用于保存和读取图像文件
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Unicode equivalents for \w and \b in Java regular expressions?
...s Regex Unicode Problems
The problem with Java regexes is that the Perl 1.0 charclass escapes — meaning \w, \b, \s, \d and their complements — are not in Java extended to work with Unicode. Alone amongst these, \b enjoys certain extended semantics, but these map neither to \w, nor to Unicode i...