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Using boolean values in C
... int bool;
#define true 1
#define false 0
Explanation
Option 1 will work only if you use C99 and it's the "standard way" to do it. Choose this if possible.
Options 2, 3 and 4 will have in practice the same identical behavior. #2 and #3 don't use #defines though, which in my opinion is better.
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Use of ~ (tilde) in R programming Language
...f the ~ are the explanatory variables. So in English you'd say something like "Species depends on Sepal Length, Sepal Width, Petal Length and Petal Width".
The myFormula <- part of that line stores the formula in an object called myFormula so you can use it in other parts of your R code.
Othe...
Is errno thread-safe?
...le is declared as extern int errno; so my question is, is it safe to check errno value after some calls or use perror() in multi-threaded code. Is this a thread safe variable? If not, then whats the alternative ?
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Postgres unique constraint vs index
...------
con_id | integer |
ind_id | integer |
Indexes:
"master_con_id_key" UNIQUE CONSTRAINT, btree (con_id)
"master_unique_idx" UNIQUE, btree (ind_id)
In table description (\d in psql) you can tell unique constraint from unique index.
Uniqueness
Let's check uniqueness, just in case.
t...
Storing C++ template function definitions in a .CPP file
...ld prefer to have stored in a CPP file instead of inline in the header. I know this can be done as long as you know which template types will be used. For example:
...
Best way to work with transactions in MS SQL Server Management Studio
...example,
Begin Transaction
-Do some T-SQL queries here.
Rollback transaction -- OR commit transaction
If you want to incorporate error handling you can do so by using a TRY...CATCH BLOCK. Should an error occur you can then rollback the tranasction within the catch block.
For example:
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How to place two divs next to each other?
...
Floating one div:
#wrapper {
width: 500px;
border: 1px solid black;
overflow: hidden; /* will contain if #first is longer than #second */
}
#first {
width: 300px;
float:left; /* add this */
border: 1px solid red;
}
#second {
border: 1px solid green;
overflow: hidden...
A Better Django Admin ManyToMany Field Widget
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BlairBlair
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Why does the order of the loops affect performance when iterating over a 2D array?
...he computer is inherently 1-dimensional. So while you imagine your array like this:
0,0 | 0,1 | 0,2 | 0,3
----+-----+-----+----
1,0 | 1,1 | 1,2 | 1,3
----+-----+-----+----
2,0 | 2,1 | 2,2 | 2,3
Your computer stores it in memory as a single line:
0,0 | 0,1 | 0,2 | 0,3 | 1,0 | 1,1 | 1,2 | 1,3 | 2,...
Method can be made static, but should it?
Resharper likes to point out multiple functions per asp.net page that could be made static. Does it help me if I do make them static? Should I make them static and move them to a utility class?
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