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Convert a row of a data frame to vector
...
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
share
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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?
...
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 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)
....
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...
libcurl的使用总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...zhu@vip.qq.com
# FileName: test_download.cpp
# Version: 1.0
# LastChange: 2010-03-09 14:20:44
# Description:
# History:
============================================*/
#include <iostream>
#include <string>
#include <vector>
#include <map>
#include “...
Formula to determine brightness of RGB color
...ewhere...
Step One:
Convert all sRGB 8 bit integer values to decimal 0.0-1.0
vR = sR / 255;
vG = sG / 255;
vB = sB / 255;
Step Two:
Convert a gamma encoded RGB to a linear value. sRGB (computer standard) for instance requires a power curve of approximately V^2.2, though the "accurate" tr...
What's the difference between equal?, eql?, ===, and ==?
... example, perform type conversion across ==, but not across eql?, so:
1 == 1.0 #=> true
1.eql? 1.0 #=> false
So you're free to override this for your own uses, or you can override == and use alias :eql? :== so the two methods behave the same way.
equal? — identity comparison
Unlike ...
How to round the corners of a button
...layer.borderColor=[uicolor blackColor].CGColor;
YourBtn1.layer.borderWidth=1.0f;
Swift 4 Solution
YourBtn1.layer.cornerRadius = YourBtn1.Frame.size.width/2
YourBtn1.layer.borderColor = UIColor.black.cgColor
YourBtn1.layer.borderWidth = 1.0
...