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How to determine if a list of polygon points are in clockwise order?
...w it works.
– Beta
Jul 27 '09 at 14:20
75
A minor caveat: this answer assumes a normal Cartesian ...
How to check if a database exists in SQL Server?
...
SteveC
12.8k2020 gold badges8282 silver badges143143 bronze badges
answered Mar 24 '09 at 20:05
eKek0eKek0
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How to hash a password
... Rfc2898DeriveBytes(password, salt, 100000);
byte[] hash = pbkdf2.GetBytes(20);
STEP 3 Combine the salt and password bytes for later use:
byte[] hashBytes = new byte[36];
Array.Copy(salt, 0, hashBytes, 0, 16);
Array.Copy(hash, 0, hashBytes, 16, 20);
STEP 4 Turn the combined salt+hash into a str...
Sorting arrays in NumPy by column
...mn of a.
– Steve Tjoa
Apr 17 '14 at 20:49
61
If you want the reverse sort, modify this to be a[a[...
Fastest way to replace NAs in a large data.table
...e a large data.table , with many missing values scattered throughout its ~200k rows and 200 columns. I would like to re code those NA values to zeros as efficiently as possible.
...
Add legend to ggplot2 line plot
... I would plot your data:
##Subset the necessary columns
dd_sub = datos[,c(20, 2,3,5)]
##Then rearrange your data frame
library(reshape2)
dd = melt(dd_sub, id=c("fecha"))
All that's left is a simple ggplot command:
ggplot(dd) + geom_line(aes(x=fecha, y=value, colour=variable)) +
scale_colour_ma...
Struct inheritance in C++
... to class Derived : private Base {}
int main()
{
Derived d;
d.x = 20; // Compiler error because inheritance is private
getchar();
return 0;
}
// Program 2
#include <stdio.h>
struct Base {
public:
int x;
};
struct Derived : Base { }; // Is equivalent to struct De...
Why is a round-trip conversion via a string not safe for a double?
...UMBER {
int precision;
int scale;
int sign;
wchar_t digits[20 + 1];
NUMBER() : precision(0), scale(0), sign(0) {}
};
#define I64(x) x##LL
static const unsigned long long rgval64Power10[] = {
// powers of 10
/*1*/ I64(0xa000000000000000),
/*2*/ I64(0xc800000000000000...
Longest line in a file
...mw] [file ...]
– Hugo
Feb 11 '16 at 20:32
12
OS X: using homebrew, use gwc for GNU Word Count gwc...
Parse a URI String into Name-Value Collection
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answered Nov 27 '12 at 20:35
Pr0gr4mm3rPr0gr4mm3r
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