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Convert array of integers to comma-separated string
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var result = string.Join(",", arr);
This uses the following overload of string.Join:
public static string Join<T>(string separator, IEnumerable<T> values);
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Getting the name of a variable as a string
This thread discusses how to get the name of a function as a string in Python:
How to get a function name as a string?
23 ...
How to append rows to an R data frame
...<- function(n){
df <- data.frame(x = numeric(n), y = character(n), stringsAsFactors = FALSE)
for(i in 1:n){
df$x[i] <- i
df$y[i] <- toString(i)
}
df
}
Here's a similar approach, but one where the data.frame is created as the last step.
# Use preallocated vectors
f4 <...
Search text in fields in every table of a MySQL database
I want to search in all fields from all tables of a MySQL database a given string, possibly using syntax as:
24 Answers
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Validating IPv4 addresses with regexp
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@PriteshAcharya Works fine over here.
– Kid Diamond
Mar 15 '18 at 13:27
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convert string array to string
I would like to convert a string array to a single string.
9 Answers
9
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Add new methods to a resource controller in Laravel
...Determine if the current route matches a given name.
*
* @param string $name
* @return bool
*/
public static function is($name)
{
return static::$app['router']->currentRouteNamed($name);
}
/**
* Determine if the current route uses a given contro...
What are the underlying data structures used for Redis?
...u asked, here is the underlying implementation of every Redis data type.
Strings are implemented using a C dynamic string library so that we don't pay (asymptotically speaking) for allocations in append operations. This way we have O(N) appends, for instance, instead of having quadratic behavior.
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Regex Named Groups in Java
...p "name"
${name} to reference to captured group in Matcher's replacement string
Matcher.group(String name) to return the captured input subsequence by the given "named group".
Other alternatives for pre-Java 7 were:
Google named-regex (see John Hardy's answer)
Gábor Lipták mentions (N...
Realistic usage of the C99 'restrict' keyword?
...ons could be saved, as mentioned by supercat.
Consider for example:
void f(char *restrict p1, char *restrict p2) {
for (int i = 0; i < 50; i++) {
p1[i] = 4;
p2[i] = 9;
}
}
Because of restrict, a smart compiler (or human), could optimize that to:
memset(p1, 4, 50);
memset(...