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What is the 'instanceof' operator used for in Java?
... Dog is Dog
dog instanceof Object // true - Object is the parent type of all objects
However, with Object animal = new Animal();,
animal instanceof Dog // false
because Animal is a supertype of Dog and possibly less "refined".
And,
dog instanceof Cat // does not even compile!
This is beca...
jQuery date/time picker [closed]
...ittle over then a little under) and I end up typing it. A keyboard is normally the easiest way to enter a precise numerical value. If you want a visual input method, a clock is the normal one for time, not a slider. Harder to implement, but might actually be useful (as long as keyboard input is a...
In JavaScript, does it make a difference if I call a function with parentheses?
I noticed a difference when calling a function with empty parentheses, or without any parentheses at all. However, I am not passing any arguments to the function so I wondered, what would be the difference between:
...
Add one row to pandas DataFrame
...
Consider adding the index to preallocate memory (see my answer)
– FooBar
Jul 23 '14 at 14:22
34
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What is the proper way to use the node.js postgresql module?
...ottleknecked based on how fast postgres
can respond to queries. It literally will line everything up, queuing
each query. Yeah, it's async and so that's alright...but wouldn't you
rather multiply your throughput by 10x? Use pg.connect set the
pg.defaults.poolSize to something sane (we do...
Real World Use of Zookeeper [closed]
...wondered whether anybody was using it currently and what they were specifically using it for storing.
13 Answers
...
Remove duplicated rows using dplyr
... @hadley I like the unique() and distinct() function, however, they all remove the 2nd duplicate from the data frame. what if I want to have all 1st encounters of the duplicate value removed? How could this be done? Thanks for any help!
– FlyingDutch
Feb...
What are the disadvantages to declaring Scala case classes?
...immutable data structures, case classes appear to be a godsend, giving you all of the following for free with just one keyword:
...
How to avoid using Select in Excel VBA
...hortcut to the Evaluate method, but this is less efficient and should generally be avoided in production code.
Set rng = [A1]
Set rng = [A1:B10]
All the above examples refer to cells on the active sheet. Unless you specifically want to work only with the active sheet, it is better to Dim a Works...
Good way of getting the user's location in Android
...k pretty well so far.
/**
* try to get the 'best' location selected from all providers
*/
private Location getBestLocation() {
Location gpslocation = getLocationByProvider(LocationManager.GPS_PROVIDER);
Location networkLocation =
getLocationByProvider(LocationManager.NETWORK_P...