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append multiple values for one key in a dictionary [duplicate]
...dictionary that looks like the following:
{
"2010": [2],
"2009": [4,7],
"1989": [8]
}
In general, it's poor programming practice to create "parallel arrays", where items are implicitly associated with each other by having the same index rather than being proper children of a container...
“Could not find any information for class named ViewController”
This bug has been driving me nuts since I started using Xcode (4.6.3). Whenever I try to link a Storyboard item to my code, I get the error:
...
How can I setup & run PhantomJS on Ubuntu?
...https://bitbucket.org/ariya/phantomjs/downloads/phantomjs-1.9.7-linux-x86_64.tar.bz2
sudo tar xjf phantomjs-1.9.7-linux-x86_64.tar.bz2
sudo ln -s /usr/local/share/phantomjs-1.9.7-linux-x86_64/bin/phantomjs /usr/local/share/phantomjs
sudo ln -s /usr/local/share/phantomjs-1.9.7-linux-x86_64/bin/phanto...
How to secure MongoDB with username and password
...
Prashant Pokhriyal
2,80944 gold badges2222 silver badges2828 bronze badges
answered Feb 2 '11 at 23:54
Alexandru PetrescuAlex...
Split string into an array in Bash
...
1144
IFS=', ' read -r -a array <<< "$string"
Note that the characters in $IFS are treated...
GCC compile error with >2 GB of code
...ces this text:
prefactor = +s.ds8*s.ds10*ti[0]->value();
expr = ( - 5/243.*(s.x14*s.x15*csc[49300] + 9/10.*s.x14*s.x15*csc[49301] +
1/10.*s.x14*s.x15*csc[49302] - 3/5.*s.x14*s.x15*csc[49303] -...
and
double csc19295 = + s.ds0*s.ds1*s.ds2 * ( -
32*s.x12pow2*s.x15*s.x34*s.mb...
What exactly is OAuth (Open Authorization)?
... |
edited Feb 8 '17 at 21:43
mandark
63355 silver badges1515 bronze badges
answered Nov 17 '10 at 4:52
...
How to toggle a value in Python
... use a conditional expression:
>>> A = [1,2,3]
>>> B = [4,5,6]
>>> x = A
>>> x = B if x == A else A
>>> x
[4, 5, 6]
>>> x = B if x == A else A
>>> x
[1, 2, 3]
>>> x = B if x == A else A
>>> x
[4, 5, 6]
Solution using...
How to append rows to an R data frame
...e the data.frame is created as the last step.
# Use preallocated vectors
f4 <- function(n) {
x <- numeric(n)
y <- character(n)
for (i in 1:n) {
x[i] <- i
y[i] <- i
}
data.frame(x, y, stringsAsFactors=FALSE)
}
microbenchmark from the "microbenchmark" package will g...
How to test equality of Swift enums with associated values
...
Swift 4.1+
As @jedwidz has helpfully pointed out, from Swift 4.1 (due to SE-0185, Swift also supports synthesizing Equatable and Hashable for enums with associated values.
So if you're on Swift 4.1 or newer, the following will au...