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What is the difference between self-types and trait subclasses?
...la> trait Wrong extends Tweeter {
| def noCanDo = name
| }
<console>:9: error: illegal inheritance;
self-type Wrong does not conform to Tweeter's selftype Tweeter with User
trait Wrong extends Tweeter {
^
<console>:10: error: not found: v...
NSString: isEqual vs. isEqualToString
What is the difference between isEqual: and isEqualToString: ?
5 Answers
5
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Plotting two variables as lines using ggplot2 on the same graph
...
The general approach is to convert the data to long format (using melt() from package reshape or reshape2) or gather()/pivot_longer() from the tidyr package:
library("reshape2")
library("ggplot2")
test_data_long <- melt(test_data, id="date") # convert to long format
ggplot(data=test_da...
How to convert list to string [duplicate]
...
@SenthilKumaran If the resulting string requires separate items such as when passing a list of files to a process, then "" has to be changed to " " (notice the space between the quotes). Otherwise, you end up with a contiguous string ("123" instead of ...
How to Rotate a UIImage 90 degrees?
...9.
// Copyright 2009 Catamount Software. All rights reserved.
//
#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
@interface UIImage (CS_Extensions)
- (UIImage *)imageAtRect:(CGRect)rect;
- (UIImage *)imageByScalingProportionallyToMinimumSize:(CGSize)targetSize;
- (UIImage *)i...
Using awk to print all columns from the nth to the last
...
As a note, although this performs the same task as the awk version, there are line buffering issues with cut, which awk doesn't have: stackoverflow.com/questions/14360640/…
– sdaau
Nov 26 '13 at 1...
How to properly seed random number generator
...ndomString(l int) string {
bytes := make([]byte, l)
for i := 0; i < l; i++ {
bytes[i] = byte(randInt(65, 90))
}
return string(bytes)
}
func randInt(min int, max int) int {
return min + rand.Intn(max-min)
}
...
'Incomplete final line' warning when trying to read a .csv file into R
...as trying to use R to read a JSON file, by using command below:
json_data<-fromJSON(paste(readLines("json01.json"), collapse=""))
; and I resolve it by my above method.
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What do the following phrases mean in C++: zero-, default- and value-initialization?
...s a class that contains POD members and is using a compiler-generated default constructor.
In C++1998 there are 2 types of initialization: zero and default
In C++2003 a 3rd type of initialization, value initialization was added.
To say they least, it's rather complex and when the diff...
Fastest way to replace NAs in a large data.table
...needed to make a local copy of the whole dataset. data.table's setkey, key<- and := do not copy-on-write.
Next, let's see where f_dowle is spending its time.
Rprof()
f_dowle(dt1)
Rprof(NULL)
summaryRprof()
$by.self
self.time self.pct total.time total.pct
"na.replace" ...