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how to find host name from IP with out login to the host
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Use nslookup
nslookup 208.77.188.166
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Non-authoritative answer:
166.188.77.208.in-addr.arpa name = www.example.com.
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What's the best way to get the last element of an array without deleting it?
... share my findings with you, benchmarked against PHP versions 5.6.38, 7.2.10 and 7.3.0RC1 (expected Dec 13 2018).
The options (<<option code>>s) I will test are:
option .1. $x = array_values(array_slice($array, -1))[0]; (as suggested by rolacja)
option .2. $x = array_slice($array, -1)...
T-SQL datetime rounded to nearest minute and nearest hours with using functions
In SQL server 2008, I would like to get datetime column rounded to nearest hour and nearest minute preferably with existing functions in 2008.
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How do I generate random numbers in Dart?
...h:
import 'dart:math';
main() {
var rng = new Random();
for (var i = 0; i < 10; i++) {
print(rng.nextInt(100));
}
}
This code was tested with the Dart VM and dart2js, as of the time of this writing.
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Create an index on a huge MySQL production table without table locking
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[2017] Update: MySQL 5.6 has support for online index updates
https://dev.mysql.com/doc/refman/8.0/en/innodb-online-ddl-operations.html#online-ddl-index-syntax-notes
In MySQL 5.6 and higher, the table remains available for...
Relative frequencies / proportions with dplyr
...n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes ...
Fill SVG path element with a background-image
...<defs>
<pattern id="img1" patternUnits="userSpaceOnUse" width="100" height="100">
<image href="wall.jpg" x="0" y="0" width="100" height="100" />
</pattern>
</defs>
Adjust the width and height according to your image, then reference it from the path like this:
&...
C++ preprocessor __VA_ARGS__ number of arguments
...
90
This is actually compiler dependent, and not supported by any standard.
Here however you have a...
Sass - Converting Hex to RGBa for background opacity
...e, this would work just fine:
@mixin background-opacity($color, $opacity: 0.3) {
background: $color; /* The Fallback */
background: rgba($color, $opacity);
}
element {
@include background-opacity(#333, 0.5);
}
If you ever need to break the hex color into RGB components, though, you ...
Browsers' default CSS for HTML elements
... { margin: 8px }
h1 { font-size: 2em; margin: .67em 0 }
h2 { font-size: 1.5em; margin: .75em 0 }
h3 { font-size: 1.17em; margin: .83em 0 }
h4, p,
blockquote, ul,
fieldset, form,
ol, dl, dir,
menu { margin: 1.12em 0 }
h5 { font-...