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Applying a function to every row of a table using dplyr?
...red May 22 '17 at 21:26
CoderGuy123CoderGuy123
4,7134646 silver badges7373 bronze badges
...
Natural Sort Order in C#
...s need to be compared section-wise, i.e., 'abc12b' should be less than 'abc123'.
– SOUser
Feb 18 '13 at 22:14
...
How do I create a unique constraint that also allows nulls?
...et_AllowNull
UNIQUE (TicketID, TicketUnique);
If IssueID 1 has ticket 123, the UNIQUE constraint will be on values (123, NULL). If IssueID 2 has no ticket, it will be on (NULL, 2). Some thought will show that this constraint cannot be duplicated for any row in the table, and still allows multip...
Is JavaScript an untyped language?
...licit compiler interjection, the instruction will error during run-time.
"12345" * 1 === 12345 // string * number => number
Strongly typed means there is a compiler, and it wants you an explicit cast from string to integer.
(int) "12345" * 1 === 12345
In either case, some compiler's featur...
Fastest sort of fixed length 6 int array
...static int seed = 76521;
while (n--) *a++ = (seed = seed *1812433253 + 12345);
}
#define NTESTS 4096
int main() {
int i;
int d[6*NTESTS];
ran_fill(6*NTESTS, d);
unsigned long long cycles = rdtsc();
for (i = 0; i < 6*NTESTS ; i+=6) {
sort6_fast(d+i);
}
cyc...
Encrypting & Decrypting a String in C# [duplicate]
... string Encrypt(string clearText)
{
string EncryptionKey = "abc123";
byte[] clearBytes = Encoding.Unicode.GetBytes(clearText);
using (Aes encryptor = Aes.Create())
{
Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, new byte[] { 0x49, 0x76...
Get Character value from KeyCode in JavaScript… then trim
...// [119]
"F9", // [120]
"F10", // [121]
"F11", // [122]
"F12", // [123]
"F13", // [124]
"F14", // [125]
"F15", // [126]
"F16", // [127]
"F17", // [128]
"F18", // [129]
"F19", // [130]
"F20", // [131]
"F21", // [132]
"F22", // [133]
"F23", // [134]
"F24", // [135]
""...
Python read-only property
... answered Sep 27 '16 at 4:31
Oz123Oz123
21.4k2222 gold badges9494 silver badges163163 bronze badges
...
Reference: Comparing PHP's print and echo
...
echo 125;
ECHO 125
multi-value echo compiles to multiple opcodes
echo 123, 456;
ECHO 123
ECHO 456
Note that multi-value echo doesn't concatenate its arguments, but outputs them one-by-one.
Reference: zend_do_print, zend_do_echo.
Runtime differences
ZEND_PRINT is implemented as follows (ps...
What's the fastest way to merge/join data.frames in R?
...bases as well.
library(plyr)
library(data.table)
library(sqldf)
set.seed(123)
N <- 1e5
d1 <- data.frame(x=sample(N,N), y1=rnorm(N))
d2 <- data.frame(x=sample(N,N), y2=rnorm(N))
g1 <- sample(1:1000, N, replace = TRUE)
g2<- sample(1:1000, N, replace = TRUE)
d <- data.frame(d1, g1,...