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How to save a data.frame in R?
...set up a column of 0's and 1's as a factor, but that save() / load() will? If so, that's something to take into account as well. I typically have a section of processing some .csv files and once I get them where I like them, I prefer to save them so I don't have to re-run that code every time I re-v...
In Java, are enum types inside a class static?
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Yes, nested enums are implicitly static.
From the language specification section 8.9:
Nested enum types are implicitly
static. It is permissable to
explicitly declare a nested enum type
to be static.
s...
How do I typedef a function pointer with the C++11 using syntax?
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It has a similar syntax, except you remove the identifier from the pointer:
using FunctionPtr = void (*)();
Here is an Example
If you want to "take away the uglyness", try what Xeo suggested:
#include <type_traits>
using FunctionPtr = std::add_pointer<void()>...
PDO get the last ID inserted
...b->prepare("...");
$stmt->execute();
$id = $db->lastInsertId();
If you want to do it with SQL instead of the PDO API, you would do it like a normal select query:
$stmt = $db->query("SELECT LAST_INSERT_ID()");
$lastId = $stmt->fetchColumn();
...
Python json.loads shows ValueError: Extra data
...)
ValueError: Extra data: line 1 column 3 - line 1 column 5 (char 2 - 4)
If you want to dump multiple dictionaries, wrap them in a list, dump the list (instead of dumping dictionaries multiple times)
>>> dict1 = {}
>>> dict2 = {}
>>> json.dumps([dict1, dict2])
'[{}, {}]...
How to get a password from a shell script without echoing
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Some shells allow you to specify the prompt for the read command: read -s -p "Password:" password
– Gordon Davisson
Oct 20 '10 at 19:40
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C++ template typedef
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using does not support specialization if I'm not wrong, so the second option is still useful in many cases.
– Utkarsh Bhardwaj
Feb 3 '16 at 14:27
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Vagrant's port forwarding not working [closed]
...omments.
First thing: try curl 'http://localhost:80' from within the VM. If that doesn't work, then it's definitely not the port forwarding.
Next: try curl -v 'http://localhost:4567/' from your host machine. Curl might give you a better error message than Safari.
I'd check that there are no fir...
If statement in aspx page
I want to write a basic if statement on my site to display either item 1 or item 2 depending on if a variable is set to true.
...
How do I create a new line in Javascript?
...than one:
document.write("\n\n\n"); // 3 new lines! My oh my!
However, if this is rendering to HTML, you will want to use the HTML tag for a newline:
document.write("<br>");
The string Hello\n\nTest in your source will look like this:
Hello!
Test
The string Hello<br><br>...