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Normalize data in pandas
...0.932785 4.535396 0.598124
In [93]: df_norm = (df - df.mean()) / (df.max() - df.min())
In [94]: df_norm
Out[94]:
a b c d
A 0.085789 -0.394348 0.337016 -0.109935
B -0.463830 0.164926 -0.650963 0.256714
C -0.158129 0.605652 -0.035090 -0.573389
D 0.536170 -0...
I want to get the type of a variable at runtime
...ble" is always present, and can be passed around as a type parameter. For example:
val x = 5
def f[T](v: T) = v
f(x) // T is Int, the type of x
But depending on what you want to do, that won't help you. For instance, may want not to know what is the type of the variable, but to know if the type o...
MySQL Conditional Insert
... DBMS does not impose limitations on which table you select from when you execute an insert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHERE user = 123
...
Convert Dictionary to semicolon separated string in c#
...
using System.Linq;
string s = string.Join(";", myDict.Select(x => x.Key + "=" + x.Value).ToArray());
(And if you're using .NET 4, or newer, then you can omit the final ToArray call.)
share
|
...
Use of 'prototype' vs. 'this' in JavaScript?
...
The examples have very different outcomes.
Before looking at the differences, the following should be noted:
A constructor's prototype provides a way to share methods and values among instances via the instance's private [[Prot...
What part of Hindley-Milner do you not understand?
...orizontal bar means that "[above] implies [below]".
If there are multiple expressions in [above], then consider them anded together; all of the [above] must be true in order to guarantee the [below].
: means has type
∈ means is in. (Likewise ∉ means "is not in".)
Γ is usually used to refer to a...
STL 算法 - C/C++ - 清泛网 - 专注C/C++及内核技术
...mplate<class InIt1, class InIt2> bool equal(InIt1 first, InIt1 last, InIt2 x);
template<class InIt1, class InIt2, class Pred> bool equal(InIt1 first, InIt1 last, InIt2 x, Pred pr);
includes
<algorithm>
判断第一个指定范围内的所有元素是否都被第二个范围包含...
How to apply a function to two columns of Pandas dataframe
...
Here's an example using apply on the dataframe, which I am calling with axis = 1.
Note the difference is that instead of trying to pass two values to the function f, rewrite the function to accept a pandas Series object, and then inde...
What's the difference between a proxy server and a reverse proxy server? [closed]
What is the difference between a proxy server and a reverse proxy server?
21 Answers
2...