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Remove rows with all or some NAs (missing values) in data.frame
...mptions --------------------
fakeData <- function(m, n, p){
set.seed(123)
m <- matrix(runif(m*n), nrow=m, ncol=n)
m[m<p] <- NA
return(m)
}
df <- cbind( data.frame(id = paste0('ID',seq(row_size)),
stringsAsFactors = FALSE),
data.frame(fak...
How big can a MySQL database get before performance starts to degrade
At what point does a MySQL database start to lose performance?
15 Answers
15
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Does the default constructor initialize built-in types?
...
For all practical purposes - no.
However for implementations that are technically compliant with the C++ standard, the answer is that it depends whether the object is POD or not and on how you initialize it.
According to the C++ standard:
MyNo...
Chrome browser reload options new feature
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I couldn't get this to work on OS X using Chrome 23.0.1271.95. Is it a Windows only feature?
– Laurent
Dec 10 '12 at 4:14
6
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HTTP status code for update and delete?
...atus code is the request sent by the client is valid (DELETE mySite/entity/123) and the entity to delete does not exist.
– Martin
Dec 30 '11 at 21:27
69
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How do I print a double value without scientific notation using Java?
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123
You could use printf() with %f:
double dexp = 12345678;
System.out.printf("dexp: %f\n", dexp)...
Can a local variable's memory be accessed outside its scope?
...n and replaced with a football stadium, and you are going to die in an explosion while you are sneaking around.
You don't know what is going to happen; when you checked out of the hotel and stole a key to illegally use later, you gave up the right to live in a predictable, safe world because you c...
What is the simplest and most robust way to get the user's current location on Android?
...ast known values.
I grab last known values from available providers and choose the most recent of them.
Here's how I use my class:
LocationResult locationResult = new LocationResult(){
@Override
public void gotLocation(Location location){
//Got the location!
}
};
MyLocation my...
sed edit file in place
I am trying to find out if it is possible to edit a file in a single sed command without manually streaming the edited content into a new file and then renaming the new file to the original file name. I tried the -i option but my Solaris system said that -i is an illegal option. Is there a d...
Why implement interface explicitly?
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