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Concurrent vs serial queues in GCD
...ou wouldn't use either of the last two for long running processes. You normally see it when you're trying to update the UI (always on the main thread) from something that may be running on another thread.
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Summarizing multiple columns with dplyr? [duplicate]
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The dplyr package contains summarise_all for this aim:
library(dplyr)
df %>% group_by(grp) %>% summarise_all(list(mean))
#> # A tibble: 3 x 5
#> grp a b c d
#> <int> <dbl> <dbl> <dbl> <dbl>
#>...
Why does git-rebase give me merge conflicts when all I'm doing is squashing commits?
...o clean up these commits by squashing many down into a single commit. Naturally, git-rebase seems the way to go. My problem is that it ends up with merge conflicts, and these conflicts are not easy to resolve. I don't understand why there should be any conflicts at all, since I'm just squashing comm...
Using std Namespace
...efined vector.
I am always against using using namespace std;. It imports all sorts of names into the global namespace and can cause all sorts of non-obvious ambiguities.
Here are some common identifiers that are in the std namespace: count, sort, find, equal, reverse. Having a local variable call...
Why fragments, and when to use fragments instead of activities?
In Android API 11+, Google has released a new class called Fragment .
11 Answers
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What are the most common naming conventions in C?
...I follow the GTK+ coding convention, which can be summarized as follows:
All macros and constants in caps: MAX_BUFFER_SIZE, TRACKING_ID_PREFIX.
Struct names and typedef's in camelcase: GtkWidget, TrackingOrder.
Functions that operate on structs: classic C style: gtk_widget_show(), tracking_order_p...
Include headers when using SELECT INTO OUTFILE?
...yourself. Something like:
SELECT 'ColName1', 'ColName2', 'ColName3'
UNION ALL
SELECT ColName1, ColName2, ColName3
FROM YourTable
INTO OUTFILE '/path/outfile'
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How to Empty Caches and Clean All Targets Xcode 4 and later
...st here: Xcode Includes .xib files that have been deleted! that cleaning all targets and empty the caches will fix the problem with Xcode including deleted .xib files but I cannot find a way to empty the cache in Xcode 4.
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How to configure multi-module Maven + Sonar + JaCoCo to give merged coverage report?
...lt;/properties>
This will make Sonar pick up unit testing reports for all submodules in the same place (a target folder in the parent project). It also tells Sonar to reuse reports ran manually instead of rolling its own. We just need to make jacoco-maven-plugin run for all submodules by placin...
Flask-SQLAlchemy how to delete all rows in a single table
How do I delete all rows in a single table using Flask-SQLAlchemy?
3 Answers
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