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Quickly reading very large tables as dataframes
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# sqldf as on SO
f <- file("test.csv")
system.time(SQLf <- sqldf("select * from f", dbname = tempfile(), file.format = list(header = T, row.names = F)))
## user system elapsed
## 10.21 0.47 10.73
ff / ffdf
require(ff)
system.time(FFDF <- read.csv.ffdf(file="test.csv",nro...
When should I use Arrow functions in ECMAScript 6?
...d consistently, everything is guaranteed to use the same thisObject as the root. If even a single standard function callback is mixed in with a bunch of arrow functions there's a chance the scope will become messed up.
Compactness: Arrow functions are easier to read and write. (This may seem opinion...
Evil Mode best practice? [closed]
...uits
(defun minibuffer-keyboard-quit ()
"Abort recursive edit.
In Delete Selection mode, if the mark is active, just deactivate it;
then it takes a second \\[keyboard-quit] to abort the minibuffer."
(interactive)
(if (and delete-selection-mode transient-mark-mode mark-active)
(setq deact...
What do the arrow icons in Subclipse mean?
... the following buttons:
- Synchronizes the local copy with the currently selected repository when clicked. Selecting from the drop-down allows switching between different remote code bases.
- Shows only incoming changes (remote → local).
- Shows only outgoing changes (local → remote).
- Sho...
How do I enable TODO/FIXME/XXX task tags in Eclipse?
...ask Tags
You can enable searching for task tags in the [Task Tags] tab and select the content types in the [Filters] tab.
For Java task tags, you should look in:
Window > Preferences > Java > Compiler > Task Tags
J.
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Android: Getting a file URI from a content URI?
In my app the user is to select an audio file which the app then handles. The problem is that in order for the app to do what I want it to do with the audio files, I need the URI to be in file format. When I use Android's native music player to browse for the audio file in the app, the URI is a cont...
How do I change the color of radio buttons?
...self consists of a round shape and a dot at the center (when the button is selected). What I want to change is the color of both. Can this be done using CSS?
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Accessing the index in 'for' loops?
...g enumerate, I switched to this approach to avoid having to write logic to select which object to enumerate.
– adg
Mar 31 '17 at 23:18
1
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Razor comment syntax
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In visual studio, select some code/markup in your razor view and press Ctrl+K, Ctrl+C, and it'll comment the selection as described above.
– MrBoJangles
Feb 17 '11 at 18:12
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JPQL IN clause: Java-Arrays (or Lists, Sets…)?
... for JPA 1.0 but you can pass a Collection in JPA 2.0:
String qlString = "select item from Item item where item.name IN :names";
Query q = em.createQuery(qlString, Item.class);
List<String> names = Arrays.asList("foo", "bar");
q.setParameter("names", names);
List<Item> actual = q.get...