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What is a “thread” (really)?
... the Instruction Pointer. For most instructions, this simply advances the IP by the size of the instruction, but control flow instructions change the IP in other, predictable ways. The sequence of values the IP takes on forms a path of execution weaving through the program code, giving rise to the...
How to convert a data frame column to numeric type?
...ertain "conversion anomaly":
# create dummy data.frame
d <- data.frame(char = letters[1:5],
fake_char = as.character(1:5),
fac = factor(1:5),
char_fac = factor(letters[1:5]),
num = 1:5, stringsAsFactors = FALSE)
Let us have a ...
Replace multiple characters in a C# string
...ssion.
s/[;,\t\r ]|[\n]{2}/\n/g
s/ at the beginning means a search
The characters between [ and ] are the characters to search for (in any order)
The second / delimits the search-for text and the replace text
In English, this reads:
"Search for ; or , or \t or \r or (space) or exactly two se...
How can I comment a single line in XML?
... parser you are using. Personally, I use an IDE (oXygen) that allows me to select a piece of XML text, right click, and ask to comment it out. Which seems a lot easier than your technique.
– Michael Kay
Jun 28 '13 at 16:54
...
how to convert from int to char*?
...
In C++17, use std::to_chars as:
std::array<char, 10> str;
std::to_chars(str.data(), str.data() + str.size(), 42);
In C++11, use std::to_string as:
std::string s = std::to_string(number);
char const *pchar = s.c_str(); //use char const* a...
How do I generate random number for each row in a TSQL Select?
...mber.
I'd suggest using convert(varbinary,newid()) as the seed argument:
SELECT table_name, 1.0 + floor(14 * RAND(convert(varbinary, newid()))) magic_number
FROM information_schema.tables
newid() is guaranteed to return a different value each time it's called, even within the same batch, so usi...
How do I concatenate two strings in C?
... some other languages have. A string in C is just a pointer to an array of char that is terminated by the first null character. There is no string concatenation operator in C.
Use strcat to concatenate two strings. You could use the following function to do it:
#include <stdlib.h>
#include &...
What is the usefulness of `enable_shared_from_this`?
...p == q);
assert(!(p < q || q < p)); // p and q must share ownership
}
The method f() returns a valid shared_ptr, even though it had no member instance. Note that you cannot simply do this:
class Y: public enable_shared_from_this<Y>
{
public:
shared_ptr<Y> f()
{
...
How to represent empty char in Java Character class
I want to represent an empty character in Java as "" in String...
15 Answers
15
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What is the difference between char * const and const char *?
...
The difference is that const char * is a pointer to a const char, while char * const is a constant pointer to a char.
The first, the value being pointed to can't be changed but the pointer can be. The second, the value being pointed at can change but t...