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C# Object Pooling Pattern implementation
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How to add a line break in an Android TextView?
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– AndroidRaji
Oct 10 '12 at 10:24
1
Misleading for not mentioning the other cha...
Java - get pixel array from image
...t.println("Testing convertTo2DUsingGetRGB:");
for (int i = 0; i < 10; i++) {
long startTime = System.nanoTime();
int[][] result = convertTo2DUsingGetRGB(hugeImage);
long endTime = System.nanoTime();
System.out.println(String.format("%-2d: %s", (i + 1), to...
Import and Export Excel - What is the best library? [closed]
...l, not CSV.
– John Scipione
Jul 20 '10 at 16:38
7
CSV falls down when exporting columns like 0345...
Drop data frame columns by name
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You can use a simple list of names :
DF <- data.frame(
x=1:10,
y=10:1,
z=rep(5,10),
a=11:20
)
drops <- c("x","z")
DF[ , !(names(DF) %in% drops)]
Or, alternatively, you can make a list of those to keep and refer to them by name :
keeps <- c("y", "a")
DF[keeps]
EDIT :
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Unique fields that allow nulls in Django
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Error installing libv8: ERROR: Failed to build gem native extension
... 'bundle'
– Sucrenoir
Feb 20 '14 at 10:29
10
This part worked but I'm still getting an error when...
Syntax for a single-line Bash infinite while loop
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Excellent! Works perfectly on Mavericks (Mac OS-X 10.9) and allows me to keep a vpn running. Openconnect disconnects after a few hours with a bad cookie error. So I put the openconnect command in a shell script, sudo su to become root, and use this cmd line: wh...
VBoxManage: error: Failed to create the host-only adapter
...rting VB works.
– Steve Bennett
Feb 10 '14 at 6:18
1
Also worked for me, VirtualBox UI showed no ...
Download file of any type in Asp.Net MVC using FileResult?
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answered Aug 31 '10 at 1:48
Ian HenryIan Henry
20.9k44 gold badges4646 silver badges5959 bronze badges
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