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How do I make a list of data frames?
...e of your choice.
GETDF_FROMLIST <- function(DF_LIST, ITEM_LOC){
DF_SELECTED <- DF_LIST[[ITEM_LOC]]
return(DF_SELECTED)
}
Now get the one you want.
D1 <- GETDF_FROMLIST(mylist, 1)
D2 <- GETDF_FROMLIST(mylist, 2)
D3 <- GETDF_FROMLIST(mylist, 3)
D4 <- GETDF_FROMLIST(mylist,...
filter for complete cases in data.frame using dplyr (case-wise deletion)
...function which lets you specify columns (basically everything which dplyr::select can understand) which should not have any NA values (modeled after pandas df.dropna()):
drop_na <- function(data, ...){
if (missing(...)){
f = complete.cases(data)
} else {
f <- complete....
How does HTTP file upload work?
...
Let's take a look at what happens when you select a file and submit your form (I've truncated the headers for brevity):
POST /upload?upload_progress_id=12344 HTTP/1.1
Host: localhost:3000
Content-Length: 1325
Origin: http://localhost:3000
... other headers ...
Conten...
Which HTTP methods match up to which CRUD methods?
...est HTTP verbs are GET, POST, PATCH, PUT and DELETE
Overview
HTTP GET - SELECT/Request
HTTP PUT - UPDATE
HTTP POST - INSERT/Create
HTTP PATCH - When PUTting a complete resource representation is cumbersome and utilizes more bandwidth, e.g.: when you have to update partially a column
HTTP DELETE ...
Understanding the Event Loop
... of queues of stuff that needs doing and every "tick" of the event loop it selects one, removes it from the queue, and runs it.
A key thing to understand is that node relies on the OS for most of the heavy lifting. So incoming network requests are actually tracked by the OS itself and when node is ...
How to write WinForms code that auto-scales to system font and dpi settings?
...ind its .exe file, right-click to edit properties, and under Compatibility
select "Override high DPI scaling behavior. Scaling performed by: System".
Be sure you never set the Font at the container level... only on the
leaf controls OR in the constructor of your most base Form if you want an applica...
Is there a hosted version of Twitter Bootstrap? [closed]
...ript, CSS, and Image files.
Additionally hosts the Font Awesome CSS and a selection of Bootswatch themes.
Maintained by @jdorfman and @mervinej.
CDNJS.com
Hosts the JavaScript, CSS and Image files. Check the GitHub repo for more specifics.
Also hosts a ton of other JS libraries, including ple...
Real escape string and PDO [duplicate]
...ing. So if people are building out queries that already have quotes like "SELECT * FROM users WHERE username = '".$conn->quote($username)."'";, the queries will inevitably fail.
– user1669496
Jun 11 '14 at 18:05
...
How to configure socket connect timeout
...ame problem by making the socket non-blocking and then putting the fd in a select/poll loop with a timeout value equal to the amount of time we are willing to wait for the connect to succeed.
I found this for Visual C++ and the explanation there also bends towards the select/poll mechanism I expla...
How do I clear the terminal screen in Haskell?
How can I clear a terminal screen after my user has selected an option from my application's menu?
8 Answers
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