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Why can I not push_back a unique_ptr into a vector?
...d Aug 15 '16 at 17:11
parker.sikand
1,3131414 silver badges2929 bronze badges
answered Jul 19 '10 at 18:15
Jam...
Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
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And if you want to convert all factor columns, you can use: model.matrix(~., data=iris)[,-1]
– user890739
Jan 5 '16 at 0:32
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How to return an array from JNI to Java?
I am attempting to use the android NDK.
4 Answers
4
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What is the argument for printf that formats a long?
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On most platforms, long and int are the same size (32 bits). Still, it does have its own format specifier:
long n;
unsigned long un;
printf("%ld", n); // signed
printf("%lu", un); // unsigned
For 64 bits, you'd want a long long:
long long n;
uns...
Pros and Cons of Interface constants [closed]
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Well, I think that it boils down to the difference between good and good enough.
While in most cases you can avoid the use of constants by implementing other patterns (strategy or perhaps flyweight), there is something to be said for not needing a half dozen other classes to represent ...
Will using goto leak variables?
... it true that goto jumps across bits of code without calling destructors and things?
1 Answer
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Is it a bad practice to use break in a for loop? [closed]
...sily-readable loops. If the body of your loop spans several screen lengths and has multiple nested sub-blocks, yes, you could easily forget that some code won't be executed after the break. If, however, the loop is short and to the point, the purpose of the break statement should be obvious.
If a l...
How to create a generic array in Java?
...i.e. its constructor was explicitly called with a Class<E> argument, and methods will throw an exception when they are passed arguments that are not of type E. See Collections.checkedCollection.
-> in that case, you should write:
public class GenSet<E> {
private E[] a;
pub...
How to store arrays in MySQL?
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The proper way to do this is to use multiple tables and JOIN them in your queries.
For example:
CREATE TABLE person (
`id` INT NOT NULL PRIMARY KEY,
`name` VARCHAR(50)
);
CREATE TABLE fruits (
`fruit_name` VARCHAR(20) NOT NULL PRIMARY KEY,
`color` VARCHAR(20),
`price` INT
)...
How do pointer to pointers work in C?
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Let's assume an 8 bit computer with 8 bit addresses (and thus only 256 bytes of memory). This is part of that memory (the numbers at the top are the addresses):
54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69
+----+----+----+----+----+----+----+...