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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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How to get file creation & modification date/times in Python?
...: Fri Jan 31 11:08:13 2020 on Linux Ubuntu 16.04!
– Färid Alijani
Jan 31 at 9:12
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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...
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...
How to log PostgreSQL queries?
...ian and Ubuntu GNU/Linux, this file usually resides at /etc/postgresql/$v/main/postgresql.conf, where $v is the server version. Also, on the aforementioned systems, when log_destination = 'stderr', the output is written to /var/log/postgresql/postgresql-$v-main.log, where $v is the server version (n...
How to allow to accept only image files?
... anything at all, so be sure to test your target platforms well.
For detailed browser support, see http://caniuse.com/#feat=input-file-accept
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What issues should be considered when overriding equals and hashCode in Java?
...iki
18 revs, 10 users 77%Antti Sykäri
12
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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:...
Maven2: Best practice for Enterprise Project (EAR file)
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So as an example you might do something like this:
<?xml version="1.0" encoding="utf-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0...