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Python integer division yields float
...perator will return integer output.
to get the result in double multiple 1.0 to "dividend or divisor"
100/35 => 2 #(Expected is 2.857142857142857)
(100*1.0)/35 => 2.857142857142857
100/(35*1.0) => 2.857142857142857
In Python 3
// => used for integer output
/ => used for doub...
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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...
What is the difference between float and double?
...+ i)
b += a;
printf("%.7g\n", b); // prints 9.000023
while
double a = 1.0 / 81;
double b = 0;
for (int i = 0; i < 729; ++ i)
b += a;
printf("%.15g\n", b); // prints 8.99999999999996
Also, the maximum value of float is about 3e38, but double is about 1.7e308, so using float can hit "infi...
What are the Ruby Gotchas a newbie should be warned about? [closed]
...eql? b # true
a.equal? b # false (a.object_id != b.object_id)
a = 1
b = 1.0
a==b # true
a.eql? b # false (a.class != b.class)
a.equal? b # false
Note that ==, eql? and equal? should always be symmetrical : if a==b then b==a.
Also note that == and eql? are both implemented in class Obj...
Is there a command like “watch” or “inotifywait” on the Mac?
...when the desktop folder of my user account is modified:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key>
&l...
How do you convert a byte array to a hexadecimal string, and vice versa?
...sing string.Concat, requires .NET 4.0) (via Will Dean)
Text: 752,078.70 (1.0X faster)
Sentence: 18.28 (2.2X faster)
{StringBuilder}.AppendFormat (using foreach) (via Tomalak)
Text: 672,115.77 (1.1X faster)
Sentence: 36.82 (1.1X faster)
{StringBuilder}.AppendFormat (using {IEnumerable}.Aggregat...
best way to add license section to iOS settings bundle
...;', $plistout) or die $!;
print $plistfh <<'EOD';
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>StringsTable</key>
...
How to change theme for AlertDialog
....AlertDialogCustom));
And then style it like you want:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<style name="AlertDialogCustom" parent="@android:style/Theme.Dialog">
<item name="android:textColor">#00FF00</item>
<item name="android:typ...
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...
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...