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Bash, no-arguments warning, and case decisions
...
if [[ $# -eq 0 ]] ; then
echo 'some message'
exit 0
fi
case "$1" in
1) echo 'you gave 1' ;;
*) echo 'you gave something else' ;;
esac
The Advanced Bash-Scripting Guide is pretty good. In spite of its name, it does treat...
javascript set a variable if undefined
...efined. It would therefore not only match undefined but also null, false, 0, NaN, "" (but not "0").
If you want to set to default only if the variable is strictly undefined then the safest way is to write:
var x = (typeof x === 'undefined') ? your_default_value : x;
On newer browsers it's actu...
How do I find if a string starts with another string in Ruby?
...
answered Nov 12 '10 at 20:02
steenslagsteenslag
71.2k1414 gold badges126126 silver badges157157 bronze badges
...
How can I truncate a datetime in SQL Server?
...e a datetime value (as to remove hours minutes and seconds) in SQL Server 2008?
13 Answers
...
Embed SVG in SVG?
...ur SVG file. For fun, save the following as recursion.svg:
<svg width="100%" height="100%" viewBox="-100 -100 200 200" version="1.1"
xmlns="http://www.w3.org/2000/svg">
<circle cx="-50" cy="-50" r="30" style="fill:red" />
<image x="10" y="20" width="80" height="80" href="recu...
How to calculate a logistic sigmoid function in Python?
... math.exp(-x))
And now you can test it by calling:
>>> sigmoid(0.458)
0.61253961344091512
Update: Note that the above was mainly intended as a straight one-to-one translation of the given expression into Python code. It is not tested or known to be a numerically sound implementation. I...
php中json_decode()和json_encode()的使用方法 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...de()和json_encode()的使用方法1.json_decode()json_decode(PHP 5 >= 5.2.0, PECL json >= 1.2.0)json_decode — 对 JSON 格式的字符串进行编码说明mixed jso...1.json_decode()
(PHP 5 >= 5.2.0, PECL json >= 1.2.0)
对 JSON 格式的字符串进行编码
说明：
mixed json_decode ...
Hour from DateTime? in 24 hours format
...he hour but show it in 24 hours format.
For example:
If the hour is 2:20:23 p.m. i want to convert it to 14:20 and that's it.
...
Format decimal for percentage values?
...se the P format string. This will vary by culture:
String.Format("Value: {0:P2}.", 0.8526) // formats as 85.26 % (varies by culture)
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Pandas get topmost n records within each group
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>>> df.groupby('id').head(2)
id value
id
1 0 1 1
1 1 2
2 3 2 1
4 2 2
3 7 3 1
4 8 4 1
(Keep in mind that you might need to order/sort before, depending on your data)
EDIT: As mentioned by the questioner, use df.gro...