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What is pseudopolynomial time? How does it differ from polynomial time?
...mon intuition for polynomial time is "time O(nk) for some k." For example, selection sort runs in time O(n2), which is polynomial time, while brute-force solving TSP takes time O(n · n!), which isn't polynomial time.
These runtimes all refer to some variable n that tracks the size of the input. Fo...
Why do people use Heroku when AWS is present? What distinguishes Heroku from AWS? [closed]
...beginner RoR programmer who's planning to deploy my app using Heroku. Word from my other advisor friends says that Heroku is really easy, good to use. The only problem is that I still have no idea what Heroku does...
...
Finding ALL duplicate rows, including “elements with smaller subscripts”
...gt;% filter(n > 1) # data frame
df %>% add_count(col1, col2) %>% select(n) > 1 # logical vector
For duplicate rows (considering all columns):
df %>% group_by_all %>% add_tally %>% ungroup %>% filter(n > 1)
df %>% group_by_all %>% add_tally %>% ungroup %>% ...
Custom fonts in iOS 7
... font you imported to your app is being packed into app itself. Do that by selecting your Target, then Build Phases, then Copy Bundle Resources. If you don't see your font in there, drag it from Supporting Files.
Finally, you would like to list all your fonts when the app starts just to see useabl...
Cannot create an NSPersistentStoreCoordinator with a nil model
...fore they aren't considered the same.
The quickest way to fix this, is to select the xcdatamodel file in your project navigator and in to the menu bar
Editor->Add Model Version...
and add a new version of your model. Make all changes to the new version.
This works in Xcode 5
...
Why use jQuery on() instead of click()
... have the same click handler that was previously bound to the same element selector, you then "delegate" the click event using on() with selector argument
To demonstrate:
http://jsfiddle.net/AJRw3/
on() can also be synonymous with click() if you don't have a selector specified:
$('.elementClass'...
Maintain/Save/Restore scroll position when returning to a ListView
... - mList.getPaddingTop());
// ...
// restore index and position
mList.setSelectionFromTop(index, top);
Explanation:
ListView.getFirstVisiblePosition() returns the top visible list item. But this item may be partially scrolled out of view, and if you want to restore the exact scroll position of t...
How do I expand the output display to see more columns of a pandas DataFrame?
...
Try this:
pd.set_option('display.expand_frame_repr', False)
From the documentation:
display.expand_frame_repr : boolean
Whether to print out the full DataFrame repr for wide DataFrames across multiple lines, max_columns is still respected, but the output will wrap-around acro...
Xcode 4.2 debug doesn't symbolicate stack call
...y setting it at the END of your didFinishLaunchingWithOptions function (or selectively disabling 3rd party libraries). Or better yet, set a symbolic break point on NSSetUncaughtExceptionHandler to quickly see who is calling it. What you may want to do is to modify your current one rather than adding...
How to determine if Javascript array contains an object with an attribute that equals a given value?
...lt;0 || splice(index, 1) here is my a bit updated code: const index = this.selected.indexOf(this.selected.find(s => s.id == passedObj.id))
– Leonid Zadorozhnykh
Aug 24 '17 at 8:27
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