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Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...hape2 and the tidyverse came plyr, with the daply function, as shown here: https://stackoverflow.com/a/7020101/210673
library(plyr)
daply(tmp, .(x, y), function(x) x$z)
## y
## x a b c
## x 1 2 3
## y 3 3 2
Using matrix indexing:
This is kinda old school but is a nice demonstration of m...
Replace transparency in PNG images with white background
....
-alpha remove -alpha off (not needed with JPG)
See documention: http://www.imagemagick.org/Usage/masking/#remove
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How do I pause my shell script for a second before continuing?
...
Run multiple sleeps and commands
sleep 5 && cd /var/www/html && git pull && sleep 3 && cd ..
This will wait for 5 seconds before executing the first script, then will sleep again for 3 seconds before it changes directory again.
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How to make Twitter bootstrap modal full screen
...infix} {
@include modal-fullscreen();
}
}
}
Demo on Codepen: https://codepen.io/andreivictor/full/MWYNPBV/
Bootstrap v3
Based on previous responses to this topic (@Chris J, @kkarli), the following generic code should work:
.modal {
padding: 0 !important; // override inline paddi...
What is a covariant return type?
...elp in preventing run-time ClassCastExceptions on returns
reference:
www.geeksforgeeks.org
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How can one see the structure of a table in SQLite? [duplicate]
... many other useful builtin dot commands -- see the documentation at http://www.sqlite.org/sqlite.html, section Special commands to sqlite3.
Example:
sqlite> entropy:~/Library/Mail>sqlite3 Envelope\ Index
SQLite version 3.6.12
Enter ".help" for instructions
Enter SQL statements terminated wit...
Type List vs type ArrayList in Java [duplicate]
...urn a list of the same type.
For example of someone getting burned, in https://stackoverflow.com/a/1481123/139985 the poster had problems with "slicing" because ArrayList.sublist(...) doesn't return an ArrayList ... and he had designed his code to use ArrayList as the type of all of his list var...
What is the largest Safe UDP Packet Size on the Internet
... by user607811, fragmentation by other network layers must be reassembled.
https://tools.ietf.org/html/rfc1122#page-56
3.3.2 Reassembly
The IP layer MUST implement reassembly of IP datagrams.
We designate the largest datagram size that can be reassembled
by EMTU_R ("Effec...
Detecting design mode from a Control's constructor
...
Another interesting method is described on that blog: http://www.undermyhat.org/blog/2009/07/in-depth-a-definitive-guide-to-net-user-controls-usage-mode-designmode-or-usermode/
Basically, it tests for the executing assembly being statically referenced from the entry assembly. It circ...
What is 'Context' on Android?
.... To understand what Context is, let’s take a look at the source code:
https://github.com/android/platform_frameworks_base/blob/master/core/java/android/content/Context.java
What exactly is Context?
Well, the documentation itself provides a rather straightforward explanation: The Context clas...