Everywhere I've tried using map, fmap has worked as well. Why did the creators of Haskell feel the need for a map function? Couldn't it just be what is currently known as fmap and fmap could be removed from the language?
Quoting from the Functor documentation at https://wiki.haskell.org/Typeclassopedia#Functor
You might ask why we need a separate map function. Why not just do
away with the current list-only map function, and rename fmap to map
instead? Well, that’s a good question. The usual argument is t...
I made a bunch of functions and an enumeration, that together allow me to write something like a switch expression. It's not as powerful as Swift switch statements, since it's lacking pattern matching and I don't intend to use this in real code, it was just an experiment. Here is what I got:
enu...
I've created a simple python meter simulator which connects to a serial port (in my case COM1) listens on the serial port and takes actions based on what it receives.
I'm looking for some advice regarding:
unnecessary / wrong logic
code that might be rewritten in a more concise / pythonic way ...
The following code doesn't work properly, I want to check after my mongoose findOne query if some subdocument in my object are defined.
function cleanIfAny(social, value) {
var name = social + '.id';
var query = {};
query[name] = value;
User.findOne(query, function (err, fou...
My naive version now is too slow. I think setting/accessing concurrent atomic bit is way slower compared to access/modify an array of boolean. Second, the parallel execution only happens on the beginning of the process. For bigger numbers, thread-pool is not really active.
public class Eratosth...
I have these two queries:
$db
->prepare("UPDATE users
SET reputation = reputation + (CASE id WHEN ? THEN 2 WHEN ? THEN 15 END),
Money = Money + (CASE id WHEN ? THEN ? WHEN ? THEN ? END)
WHERE id IN (?, ?); ")
->execute(array($author_ques_id, ...
There is a full featured support of countable sets in .NET: IEnumerable<T>. What about uncountable sets; sets defined by predicate? How can they be manipulated and interact with IEnumerable<T>?
Demo (you can click fork here and play with it online):
using static System.Console;
using static Sys...
I have a method that generates some html, but it looks ugly to me. Maybe there are some better solutions for this?
public static string GetReview(Quiz quiz)
{
StringBuilder sb = new StringBuilder();
string questionSection = string.Format(
"<div class=\"alert ale...
I'm working on converting a simple Python script into nodejs 4.4.5 with es6 features like Promises.
The original Python script did the following:
Contact a 3rd party SOAP service
Attempt to retrieve results by calling various SOAP methods
Display the results as a page that can be monitored by ...
I've written the following code to take data from the Excel file "Data" and use it for a mailmerge in a prepare Word template named "Template." I'm new to using VBA in word or Access, so any feedback in these areas is very welcome
Sub AccessTransfer()
Dim strPath As String
Dim objAccess As Acce...
The following function represents the electrostatic potential, in spherical coordinates, due to a ring of charge \$q=1\$ and radius \$R=1\$, placed in the plane \$x\$-\$y\$:
$$\phi(r,\theta) = \sum_{n=0}^\infty \frac{r_\min^n}{r_\max^{n+1}} P_n(\cos\theta) P_n(0) $$
where \$P_n\$ are the Legend...
Right now this function takes an excessively long time to run, please let me know how to make it more efficient.
lunarCal is 144x7 and the dput for it is here.
Here's the code:
if(!require(pacman)) install.packages("pacman")
pacman::p_load(lubridate)
cat("Please make sure that birthday inputs ...
Last time when I tried to come up with something easy that wasn't a duplicate, it ended up being way too hard.. So hopefully this time it's indeed something newcomers can try as well.
Input:
An array/list with integers/decimals. (Or a string representing an array with integers/decimals.)
Outpu...
I am creating a forum. It has sections. Each section has its own groups. I want to fetch all sections and their groups. But there is a problem with my code. plz check and tell me where the fault is.
<?php
// Database Configuration
$_db['host'] = 'localhost';
$_db['user'] = 'root';
$_db['pas...
write a program in python language by take a 10 digit number from user and print the number of even numbers and odd numbers of that 10 digit number
for example let the number be 1256986314 so
even number in this 10 digit number is 5
and odd number in this 10 digit number is 5
