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How to resolve “must be an instance of string, string given” prior to PHP 7?
... supposed to work to begin with. Given the dynamic typing system, this actually makes some sort of perverted sense.
You can only manually "type hint" scalar types:
function foo($string) {
if (!is_string($string)) {
trigger_error('No, you fool!');
return;
}
...
}
...
Calculate distance between 2 GPS coordinates
...y solution:
#include <math.h>
#include "haversine.h"
#define d2r (M_PI / 180.0)
//calculate haversine distance for linear distance
double haversine_km(double lat1, double long1, double lat2, double long2)
{
double dlong = (long2 - long1) * d2r;
double dlat = (lat2 - lat1) * d2r;
...
Why do x86-64 systems have only a 48 bit virtual address space?
...
Because that's all that's needed. 48 bits give you an address space of 256 terabyte. That's a lot. You're not going to see a system which needs more than that any time soon.
So CPU manufacturers took a shortcut. They use an instruction set...
How do I abort the execution of a Python script? [duplicate]
...
Prints "aa! errors!" and exits with a status code of 1.
There is also an _exit() function in the os module. The sys.exit() function raises a SystemExit exception to exit the program, so try statements and cleanup code can execute. The os._exit() version doesn't do this. It just ends the program...
Dictionaries and default values
...collections import defaultdict
a = defaultdict(lambda: "default", key="some_value")
a["blabla"] => "default"
a["key"] => "some_value"
You can pass any ordinary function instead of lambda:
from collections import defaultdict
def a():
return 4
b = defaultdict(a, key="some_value")
b['absent...
Sending Email in Android using JavaMail API without using the default/built-in app
...net.ssl.SSLSocketFactory");
props.put("mail.smtp.socketFactory.fallback", "false");
props.setProperty("mail.smtp.quitwait", "false");
session = Session.getDefaultInstance(props, this);
}
protected PasswordAuthentication getPasswordAuthentication()...
Assignment in an if statement
... = value as T;
if (t != null)
{
action(t);
}
}
Then call it with:
animal.AsIf<Dog>(dog => {
// Use dog in here
});
Alternatively, you could combine the two:
public static void AsIf<T>(this object value, Action<T> action) where T : class
{
// EVI...
Send message to specific client with socket.io and node.js
..."I'm the master", function() {
// Save the socket id to Redis so that all processes can access it.
client.set("mastersocket", socket.id, function(err) {
if (err) throw err;
console.log("Master socket is now" + socket.id);
});
});
socket.on("message to master", function(...
Efficient evaluation of a function at every cell of a NumPy array
...t be faster than the "manual" double loop iteration and assignment through all the array elements. Especially, because it stores the result to a newly created variable (and not directly to the initial input). Thanks a lot for your reply though:)
– Peter
Oct 9 '...
Find unique rows in numpy.array
...e((np.void, a.dtype.itemsize * a.shape[1]))) ?
– Akavall
Jun 7 '13 at 0:28
3
@Akavall It is creat...