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Pandas convert dataframe to array of tuples
...
list(data_set.itertuples(index=False))
As of 17.1, the above will return a list of namedtuples.
If you want a list of ordinary tuples, pass name=None as an argument:
list(data_set.itertuples(index=False, name=None))
...
Append an object to a list in R in amortized constant time, O(1)?
... for(i in 1:n) {a <- list(a, list(i))}
},
by_index = {
a <- list(0)
for(i in 1:n) {a[length(a) + 1] <- i}
a
},
append_ = {
a <- list(0)
for(i in 1:n) {a <- append(a, i)}
...
Select first row in each GROUP BY group?
...otal can be NULL (won't hurt either way, but you'll want to match existing indexes):
...
ORDER BY customer, total DESC NULLS LAST, id;
Major points
DISTINCT ON is a PostgreSQL extension of the standard (where only DISTINCT on the whole SELECT list is defined).
List any number of expressions in the ...
Understanding slice notation
...as Dataframes both the start and the stop are included when present in the index. For further info see the Pandas indexing documentation.
– vreyespue
May 29 '19 at 12:54
...
PhoneGap: Detect if running on desktop browser
...n a browser or not, here is another great option:
var app = document.URL.indexOf( 'http://' ) === -1 && document.URL.indexOf( 'https://' ) === -1;
if ( app ) {
// PhoneGap application
} else {
// Web page
}
as seen here: Detect between a mobile browser or a PhoneGap application...
Invalid argument supplied for foreach()
...
Personally I find this to be the most clean - not sure if it's the most efficient, mind!
if (is_array($values) || is_object($values))
{
foreach ($values as $value)
{
...
}
}
The reason for my preference is it...
Memoization in Haskell?
...
We can do this very efficiently by making a structure that we can index in sub-linear time.
But first,
{-# LANGUAGE BangPatterns #-}
import Data.Function (fix)
Let's define f, but make it use 'open recursion' rather than call itself directly.
f :: (Int -> Int) -> Int -> Int
f...
MD5 algorithm in Objective-C
... char *resultData = malloc(CC_MD5_DIGEST_LENGTH * 2 + 1);
for (uint index = 0; index < CC_MD5_DIGEST_LENGTH; index++) {
resultData[index * 2] = HexEncodeChars[(result[index] >> 4)];
resultData[index * 2 + 1] = HexEncodeChars[(result[index] % 0x10)];
}
resultDa...
What is Java EE? [duplicate]
...ed in the Java SE Platform. (docs.oracle.com/javase/tutorial/jndi/software/index.html#JDK).
– ROMANIA_engineer
Nov 19 '15 at 11:38
...
What is an example of the simplest possible Socket.io example?
...r updated small-small for the newer API.
Just because I feel nice today:
index.html
<!doctype html>
<html>
<head>
<script src='/socket.io/socket.io.js'></script>
<script>
var socket = io();
socket.on('welcome', funct...