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How to calculate a logistic sigmoid function in Python?
...uld do it:
import math
def sigmoid(x):
return 1 / (1 + math.exp(-x))
And now you can test it by calling:
>>> sigmoid(0.458)
0.61253961344091512
Update: Note that the above was mainly intended as a straight one-to-one translation of the given expression into Python code. It is not t...
Extract substring in Bash
...he form someletters_12345_moreleters.ext , I want to extract the 5 digits and put them into a variable.
22 Answers
...
Convert NSArray to NSString in Objective-C
... @TechZen - no, because [array description] inserts newlines and the outer parentheses.
– Dave DeLong
Dec 1 '09 at 21:05
...
Why use the yield keyword, when I could just use an ordinary IEnumerable?
...azy. Only, it requires far less compiler generated custom ---gunk--- code. And less developer time writing and maintaining. (Of course, that was just this example)
– sehe
Dec 28 '12 at 11:57
...
`levels
...answers here are good, but they are missing an important point. Let me try and describe it.
R is a functional language and does not like to mutate its objects. But it does allow assignment statements, using replacement functions:
levels(x) <- y
is equivalent to
x <- `levels<-`(x, y)
...
How large should my recv buffer be when calling recv in the socket library
...atagram socket (SOCK_DGRAM) - within TCP/IP, the former corresponds to TCP and the latter to UDP.
How do you know how big to make the buffer passed to recv()?
SOCK_STREAM: It doesn't really matter too much. If your protocol is a transactional / interactive one just pick a size that can hold the ...
How to convert a number to string and vice versa in C++
...
Update for C++11
As of the C++11 standard, string-to-number conversion and vice-versa are built in into the standard library. All the following functions are present in <string> (as per paragraph 21.5).
string to numeric
float stof(const s...
Django MEDIA_URL and MEDIA_ROOT
I'm trying to upload an image via the Django admin and then view that image either in a page on the frontend or just via a URL.
...
displayname attribute vs display attribute
What is difference between DisplayName attribute and Display attribute in ASP.NET MVC?
4 Answers
...
How to do the equivalent of pass by reference for primitives in Java
...lass member variable.
Choice 4: Create a single element array of type int and pass that
This is considered a hack, but is sometimes employed to return values from inline class invocations.
void play(int [] toyNumber){
System.out.println("Toy number in play " + toyNumber[0]);
toyNumbe...