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How to resize an image with OpenCV2.0 and Python2.6
...lf ?
– user4772964
Apr 22 '15 at 16:32
8
Yes, you can't reduce the size of the image without losi...
What's the difference between assignment operator and copy constructor?
...tialized object from some other object's data.
A(const A& rhs) : data_(rhs.data_) {}
For example:
A aa;
A a = aa; //copy constructor
An assignment operator is used to replace the data of a previously initialized object with some other object's data.
A& operator=(const A& rhs) {...
Introducing FOREIGN KEY constraint may cause cycles or multiple cascade paths - why?
...s Either the extension methods changed over time or you forgot the builder _ .Entity<TEntity>() _ before HasOne() can be called...
– ViRuSTriNiTy
May 18 at 13:51
1
...
What is a NullReferenceException, and how do I fix it?
...t value when a null is encountered:
IService CreateService(ILogger log, Int32? frobPowerLevel)
{
var serviceImpl = new MyService(log ?? NullLog.Instance);
// Note that the above "GetValueOrDefault()" can also be rewritten to use
// the coalesce operator:
serviceImpl.FrobPowerLevel = fr...
Evaluating a mathematical expression in a string
...I've rewrapped fourFn into a numeric parser class for easier reuse.
from __future__ import division
from pyparsing import (Literal, CaselessLiteral, Word, Combine, Group, Optional,
ZeroOrMore, Forward, nums, alphas, oneOf)
import math
import operator
__author__ = 'Paul McGu...
What is an optional value in Swift?
...ion.
– return true
Apr 24 '15 at 14:32
...
filter for complete cases in data.frame using dplyr (case-wise deletion)
... %>% filter(complete.cases(.))
or this:
library(tidyr)
df %>% drop_na
If you want to filter based on one variable's missingness, use a conditional:
df %>% filter(!is.na(x1))
or
df %>% drop_na(x1)
Other answers indicate that of the solutions above na.omit is much slower but tha...
Typedef function pointer?
...p;square.
– pranavk
Mar 5 '13 at 13:32
2
Question, in your first typedef example you have of the ...
How do I concatenate two arrays in C#?
...e.
– Jon Schneider
Feb 20 '15 at 19:32
1
This is what happens without the toArray() Cannot impli...
How to generate a random number in C++?
...d
(assuming rand() itself is uniformly distributed from 0 to RAND_MAX) */
while( ( n = rand() ) > RAND_MAX - (RAND_MAX-5)%6 )
{ /* bad value retrieved so get next one */ }
printf( "%d,\t%d\n", n, n % 6 + 1 );
}
return 0;
}
^^^ THAT sequence from a sing...