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Define all functions in one .R file, call them from another .R file. How, if possible?
... these files are in your current working directory.
If abc.R is:
fooABC <- function(x) {
k <- x+1
return(k)
}
and xyz.R is:
fooXYZ <- function(x) {
k <- fooABC(x)+1
return(k)
}
then this will work:
> source("abc.R")
> source("xyz.R")
> fooXYZ(3)
[1] 5
>...
php $_POST array empty upon form submission
I have a custom CMS i've built that works perfectly on my dev box (Ubuntu/PHP5+/MySQL5+).
27 Answers
...
Unique Key constraints for multiple columns in Entity Framework
...e void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Entity>()
.HasIndex(p => new {p.FirstColumn , p.SecondColumn}).IsUnique();
}
The second approach to create Unique Constraints with EF Core by using Alternate Keys.
Examples
One column:
modelBuilder.Entity<...
Generic method multiple (OR) type constraint
...is , I learned it was possible to allow a method to accept parameters of multiple types by making it a generic method. In the example, the following code is used with a type constraint to ensure "U" is an IEnumerable<T> .
...
How do you make a web application in Clojure? [closed]
...
(def app [req]
(if (= "/home" (:uri req))
{:status 200
:body "<h3>Welcome Home</h3>"}
{:status 200
:body "<a href='/home'>Go Home!</a>"}))
One other part of Ring is the concept of middle-ware. This is code that sits between the handler and the incoming...
How to get an IFrame to be responsive in iOS Safari?
...ame would be responsive as well. In theory it's simple, simply aider use <iframe width="100%"></iframe> or set the CSS width to iframe { width: 100%; } however in practice it's not quite that simple, but it can be.
...
Static member initialization in a class template
...
Just define it in the header:
template <typename T>
struct S
{
static double something_relevant;
};
template <typename T>
double S<T>::something_relevant = 1.5;
Since it is part of a template, as with all templates the compiler will make su...
GIT clone repo across local file system in windows
...file protocol. This requires you to use four slashes:
git clone file:////<host>/<share>/<path>
For example, if your main machine has the IP 192.168.10.51 and the computer name main, and it has a share named code which itself is a git repository, then both of the following comman...
What's the difference between Sender, From and Return-Path?
... (look at paragraph 2.1.2. and the following)
2.1.2. Header Field: From
Description:
Mailbox of message author
[...]
Related information:
Specifies the author(s) of the message; that is, the mailbox(es)
of the person(s) or system(s) responsible for the writing of the
message. ...
What is the difference between ${var}, “$var”, and “${var}” in the Bash shell?
...cording to the bash manual:
Referencing an array variable without a subscript is equivalent to referencing the array with a subscript of 0.
In other words, if you don't supply an index with [], you get the first element of the array:
foo=(a b c)
echo $foo
# a
Which is exactly the same as
f...