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How to drop columns by name in a data frame
...is not needed for a one column dataframe (because df['myColumns'] will get casted to a vector if needed).
– Antoine Lizée
Aug 3 '15 at 18:08
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How to disable GCC warnings for a few lines of code
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Another pattern is to just do a cast of the variable to void. In fact, I have seen in a project the following macro: #define UNUSED(x) ((void)x) used to silence warnings. I think it was in ReactOS?
– Paul Stelian
Apr 1...
How to speed up insertion performance in PostgreSQL
...h statement using SQLSetConnectAttr(conn, SQL_ATTR_AUTOCOMMIT, reinterpret_cast<SQLPOINTER>(SQL_AUTOCOMMIT_OFF), 0);
Once all rows have been inserted, commit the transaction using SQLEndTran(SQL_HANDLE_DBC, conn, SQL_COMMIT);. There is no need to explicitly open a transaction.
Unfortunately,...
How to use C++ in Go
... to the bridge's implementation
Foo* AsFoo(void* foo) { return reinterpret_cast<Foo*>(foo); }
void LIB_DestroyFoo(void* foo) {
std::cout << "[c++ bridge] LIB_DestroyFoo(" << foo << ")" << std::endl;
AsFoo(foo)->~Foo();
}
int LIB_FooValue(void* foo) {
std::cou...
How do you create a random string that's suitable for a session ID in PostgreSQL?
...th of the string.
PostgreSQL nifty UUID comes with some default operators, castings, and features.
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Is there a way to change the environment variables of another process in Unix?
...ystems gdb may give the following error: 'putenv' has unknown return type; cast the call to its declared return type; in those cases you should change putenv call to this: call (int) putenv ("env_var_name=env_var_value")
– Emir Uner
Feb 20 '19 at 9:33
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Storing money in a decimal column - what precision and scale?
...onverting a floating point number back to an integer in step 3, don't just cast it - use a math function to round it first. This will usually be round, though in special cases it could be floor or ceil. Know the difference and choose carefully.
Store the type of a number alongside the value
This m...
How do I create delegates in Objective-C?
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I think you need to cast the unsigned int type to BOOL as the return value of delegate respondsToSelector is of type BOOL.
– Roland
Nov 25 '13 at 8:34
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Math.random() versus Random.nextInt(int)
...ution.
Scaling by 6 doesn't alter the number of possible values, and casting to an int then forces these values into one of six 'buckets' (0, 1, 2, 3, 4, 5), each bucket corresponding to ranges encompassing either 1501199875790165 or 1501199875790166 of the possible values (as 6 is not a disvi...
Is there a better alternative than this to 'switch on type'?
...ching-on-types
Short version: TypeSwitch is designed to prevent redundant casting and give a syntax that is similar to a normal switch/case statement. For example, here is TypeSwitch in action on a standard Windows form event
TypeSwitch.Do(
sender,
TypeSwitch.Case<Button>(() => te...