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Paste multiple columns together
...c('d', 'e', 'f'),
'd' = c('g', 'h', 'i'))
tidyr::unite_(data, paste(colnames(data)[-1], collapse="_"), colnames(data)[-1])
a b_c_d
1 1 a_d_g
2 2 b_e_h
3 3 c_f_i
Edit: Exclude first column, everything else gets pasted.
# tidyr_0.6.3
unite(data, newCol, -a)
# or by colum...
How can jQuery deferred be used?
...he new Deferred object and the attached methods .when , .Deferred and ._Deferred .
11 Answers
...
How should I call 3 functions in order to execute them one after the other?
...we have three asynchronous functions that we want to execute in order, some_3secs_function, some_5secs_function, and some_8secs_function.
Since functions can be passed as arguments in Javascript, you can pass a function as a callback to execute after the function has completed.
If we create the fu...
Does Swift have documentation generation support?
...// You can use bulleted lists (use `-`, `+` or `*`):
///
/// - Text can be _emphasised_
/// - Or **strong**
///
/// Or numbered lists:
///
/// 7. The numbers you use make no difference
/// 0. The list will still be ordered, starting from 1
/// 5. But be sensible and just use 1, 2, 3 etc…
///
/// -...
Excel: last character/string match in a string
...st came up with this solution, no VBA needed;
Find the last occurance of "_" in my example;
=IFERROR(FIND(CHAR(1);SUBSTITUTE(A1;"_";CHAR(1);LEN(A1)-LEN(SUBSTITUTE(A1;"_";"")));0)
Explained inside out;
SUBSTITUTE(A1;"_";"") => replace "_" by spaces
LEN( *above* ) => count the chars
LEN(A1)...
Passing $_POST values with cURL
How do you pass $_POST values to a page using cURL ?
8 Answers
8
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Leaflet - How to find existing markers, and delete markers?
...
The layers are internally stored in map._layers.
– flup
Jan 26 '13 at 14:51
11
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What is the most efficient way to deep clone an object in JavaScript?
...actical.
class StructuredCloner {
constructor() {
this.pendingClones_ = new Map();
this.nextKey_ = 0;
const channel = new MessageChannel();
this.inPort_ = channel.port1;
this.outPort_ = channel.port2;
this.outPort_.onmessage = ({data: {key, value}}) => {
const r...
What is a proper naming convention for MySQL FKs?
...ue name automatically.
In any case, this is the convention that I use:
fk_[referencing table name]_[referenced table name]_[referencing field name]
Example:
CREATE TABLE users(
user_id int,
name varchar(100)
);
CREATE TABLE messages(
message_id int,
user_id int
);
...
Android Gallery on Android 4.4 (KitKat) returns different URI for Intent.ACTION_GET_CONTENT
Before KitKat (or before the new Gallery) the Intent.ACTION_GET_CONTENT returned a URI like this
19 Answers
...