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Convert a row of a data frame to vector
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I recommend unlist, which keeps the names.
unlist(df[1,])
a b c
1.0 2.0 2.6
is.vector(unlist(df[1,]))
[1] TRUE
If you don't want a named vector:
unname(unlist(df[1,]))
[1] 1.0 2.0 2.6
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Random float number generation
... employ a more advanced method.
This will generate a number from 0.0 to 1.0, inclusive.
float r = static_cast <float> (rand()) / static_cast <float> (RAND_MAX);
This will generate a number from 0.0 to some arbitrary float, X:
float r2 = static_cast <float> (rand()) / (static...
Trying to start a service on boot on Android
...ervice on device boot(autorun app, etc.)
For first: since version Android 3.1+ you don't receive BOOT_COMPLETE if user never started your app at least once or user "force closed" application.
This was done to prevent malware automatically register service. This security hole was closed in newer ver...
Where are my postgres *.conf files?
...1h
#checkpoint_completion_target = 0.5 # checkpoint target duration, 0.0 - 1.0
#checkpoint_warning = 30s # 0 disables
# - Archiving -
#archive_mode = off # allows archiving to be done
# (change requires restart)
#archive_command = '' # command to use to archive a lo...
Do Git tags only apply to the current branch?
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If you create a tag by e.g.
git tag v1.0
the tag will refer to the most recent commit of the branch you are currently on. You can change branch and create a tag there.
You can also just refer to the other branch while tagging,
git tag v1.0 name_of_other_bran...
Determine the line of code that causes a segmentation fault?
...en if that memory area was accessible to the process.
¹ That is Clang 3.1+ and GCC 4.8+.
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Calculate difference in keys contained in two Python dictionaries
... in dicta.keys(): => for key in dicta:
– Jean-François Fabre♦
May 24 '18 at 19:51
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How to change shape color dynamically?
...n specify backgroundTint for the ImageView.
circle.xml
<?xml version="1.0" encoding="utf-8"?>
<shape
xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="oval">
</shape>
And in your layout:
<ImageView
android:layout_width="50dp"
android:...
Asynchronous vs Multithreading - Is there a difference?
...synchronous processing since the non preemptive times (versions 2.13, 3.0, 3.1, etc) using the message loop, way before supporting real threads. So to answer your question, no, it is not necessary to create a thread to perform asynchronous processing.
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Bash Templating: How to build configuration files from templates with Bash?
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NOTE: Apparently a there was a change from bash 3.1 to 3.2 (and up) in which the single quotes around the regex - treat the contents of the regex as a string literal. So the regex above should be... (\$\{[a-zA-Z_][a-zA-Z_0-9]*\}) stackoverflow.com/questions/304864/…
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