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Order data frame rows according to vector with specific order
...ame),]
name value
2 b TRUE
3 c FALSE
1 a TRUE
4 d FALSE
It will work as long as your target contains exactly the same elements as df$name, and neither contain duplicate values.
From ?match:
match returns a vector of the positions of (first) matches of its first argument
in its ...
Two way sync with rsync
...uto dirA/ dirB/
unison -batch dirA/ dirB/ asks no questions at all, and writes to output how many files were ignored (because they conflicted).
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Difference between break and continue in PHP?
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break ends a loop completely, continue just shortcuts the current iteration and moves on to the next iteration.
while ($foo) { <--------------------┐
continue; --- goes back here --┘
break; ----- jumps here ----┐
} |
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Making a UITableView scroll when text field is selected
...d error, I'm giving up and asking the question. I've seen a lot of people with similar problems but can't get all the answers to work right.
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How to get ID of the last updated row in MySQL?
...value', id = (SELECT @update_id := id)
WHERE some_other_column = 'blah' LIMIT 1;
SELECT @update_id;
EDIT by aefxx
This technique can be further expanded to retrieve the ID of every row affected by an update statement:
SET @uids := null;
UPDATE footable
SET foo = 'bar'
WHERE fooid > 5
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How to make my font bold using css?
...follow
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edited Mar 29 '12 at 10:20
Mathias Bynens
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Delete keychain items when an app is uninstalled
...mple:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
//Clear keychain on first run in case of reinstallation
if (![[NSUserDefaults standardUserDefaults] objectForKey:@"FirstRun"]) {
// Delete values from keychain here
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POSTing JsonObject With HttpClient From Web API
...m trying to POST a JsonObject using HttpClient from Web API. I'm not quite sure how to go about this and can't find much in the way of sample code.
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How do I reload .bashrc without logging out and back in?
If I make changes to .bashrc , how do I reload it without logging out and back in?
17 Answers
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Setting DIV width and height in JavaScript
I have a div with id="div_register" . I want to set its width dynamically in JavaScript.
6 Answers
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