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How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
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edited Jul 15 at 20:25
answered Aug 2 '09 at 13:35
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How to get row from R data.frame
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130
x[r,]
where r is the row you're interested in. Try this, for example:
#Add your data
x <-...
What's with 181783497276652981 and 8682522807148012 in Random (Java 7)?
Why were 181783497276652981 and 8682522807148012 chosen in Random.java ?
3 Answers
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Should one use < or
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The first is more idiomatic. In particular, it indicates (in a 0-based sense) the number of iterations. When using something 1-based (e.g. JDBC, IIRC) I might be tempted to use <=. So:
for (int i=0; i < count; i++) // For 0-based APIs
for (int i=1; i <= count; i++) // For 1-ba...
How to open, read, and write from serial port in C?
...ity)
{
struct termios tty;
if (tcgetattr (fd, &tty) != 0)
{
error_message ("error %d from tcgetattr", errno);
return -1;
}
cfsetospeed (&tty, speed);
cfsetispeed (&tty, speed);
tty.c_cflag = (tty.c_...
Regular expression for a hexadecimal number?
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How about the following?
0[xX][0-9a-fA-F]+
Matches expression starting with a 0, following by either a lower or uppercase x, followed by one or more characters in the ranges 0-9, or a-f, or A-F
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How can I check if character in a string is a letter? (Python)
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AMC
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answered Mar 21 '13 at 21:24
rainerrainer
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Set operations (union, intersection) on Swift array?
...tring> = Set(array1)
let set2:Set<String> = Set(array2)
Swift 3.0+ can do operations on sets as:
firstSet.union(secondSet)// Union of two sets
firstSet.intersection(secondSet)// Intersection of two sets
firstSet.symmetricDifference(secondSet)// exclusiveOr
Swift 2.0 can calculate on ar...
What do 'real', 'user' and 'sys' mean in the output of time(1)?
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2130
Real, User and Sys process time statistics
One of these things is not like the other. Real ref...
Add zero-padding to a string
How do I add "0" padding to a string so that my string length is always 4?
5 Answers
5...