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passing several arguments to FUN of lapply (and others *apply)
I have a question regarding passing multiple arguments to a function, when using lapply in R .
4 Answers
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C++ performance challenge: integer to std::string conversion
...
Ah, awesome challenge by the way... I've had a lot of fun with this.
I have two algorithms to submit (code is at the bottom if you feel like skipping to it). In my comparisons I require that the function return a string and that it can handle int and unsigned int. Comparing thi...
Linq code to select one item
...e extension methods directly like:
var item = Items.First(i => i.Id == 123);
And if you don't want to throw an error if the list is empty, use FirstOrDefault which returns the default value for the element type (null for reference types):
var item = Items.FirstOrDefault(i => i.Id == 123);
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Is there a way to pass optional parameters to a function?
Is there a way in Python to pass optional parameters to a function while calling it and in the function definition have some code based on "only if the optional parameter is passed"
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How to compile a static library in Linux?
...e lib
#include <stdio.h>
#include "lib.h"
int main ( void )
{
fun1(10);
fun2(10);
return 0;
}
lib.h the libs main header
#ifndef LIB_H_INCLUDED
#define LIB_H_INCLUDED
#include "lib1.h"
#include "lib2.h"
#endif
lib1.c first lib source
#include "lib1.h"
#include <stdio...
How can I use speech recognition without the annoying dialog in android phones
... object : ConversionCallback {
override fun onSuccess(result: String) {
sttOutput.text = result
}
override fun onCompletion() {
}
...
Detect if value is number in MySQL
...l1 * 1) = col1
It doesn't work for non-standard numbers like
1e4
1.2e5
123. (trailing decimal)
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MySQL Conditional Insert
...nsert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHERE user = 123
AND item = 456)
In this, dual is a table with one row only (found orig...
Java Generics (Wildcards)
...me pretty good explanations of generics in the articles Wildcards and More Fun with Wildcards.
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