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Remove columns from dataframe where ALL values are NA
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dplyr now has a select_if verb that may be helpful here:
library(dplyr)
temp <- data.frame(x = 1:5, y = c(1,2,NA,4, 5), z = rep(NA, 5))
not_all_na <- function(x) any(!is.na(x))
not_any_na <- function(x) all(!is.na(x))
> temp
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TextView Marquee not working [duplicate]
...oid:freezesText="true">
Edit (on behalf of Adil Hussain):
textView.setSelected(true) needs to be set in code behind for this to work.
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follo...
MySQL OPTIMIZE all tables?
...>.<your_table>;, optimize all tables in a given schema like this: select concat('OPTIMIZE NO_WRITE_TO_BINLOG TABLE ',table_schema,'.',table_name,';') into outfile '/tmp/optimize_all_tables.sql' from information_schema.tables where table_schema = 'pabeta' and table_type = 'base table'; sourc...
How to get a list of all files that changed between two Git commits?
...om the git diff documentation:
diff-filter=[(A|C|D|M|R|T|U|X|B)…[*]]
Select only files that are Added (A), Copied (C), Deleted (D), Modified (M), Renamed (R), have their type (i.e. regular file, symlink, submodule, …) changed (T), are Unmerged (U), are Unknown (X), or have had their pairi...
Why all the Active Record hate? [closed]
...need to write raw SQL, it's easily done.
@Tim Sullivan
...and you select several instances of the model, you're basically doing a "select * from ..."
Code:
people = Person.find(:all, :select=>'name, id')
This will only select the name and ID columns from the database, all the other ...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...a decent programming background but my SQL experience is limited mostly to SELECT queries
– Rob
Jul 3 '12 at 14:47
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Visual Studio, debug one of multiple threads
...ow (Debug -> Windows -> Threads) right-click the thread you want and select "switch to thread".
You can also choose "freeze" on the threads you don't want to debug in order to keep them from running. Don't forget to "thaw" them if you expect them to do work, however.
Further reading.
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Remove all unused resources from an android project
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OR
In Android Studio Menu > Refactor > Remove Unused Resources...
Select the resources you want to remove. You can exclude resources you want to keep by right-clicking on the resource item.
Use Do Refactor to remove all Resources at once.
Update: use ⌘OptionShifti for mac
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What's an easy way to read random line from a file in Unix command line?
...he whole file needs to get shuffled by sort before piping it to head. shuf selects random lines from the file, instead and is much faster for me.
– Bengt
Nov 25 '12 at 17:33
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CSS: background image on background color
I have panel which I colored blue if this panel is being selected (clicked on it). Additionally, I add a small sign ( .png image) to that panel, which indicates that the selected panel has been already selected before.
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