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Convert JS date time to MySQL datetime
...nction to pad numbers to two digits…
**/
function twoDigits(d) {
if(0 <= d && d < 10) return "0" + d.toString();
if(-10 < d && d < 0) return "-0" + (-1*d).toString();
return d.toString();
}
/**
* …and then create the method to output the date string as ...
Running a cron job at 2:30 AM everyday
How to configure a cron job to run every night at 2:30? I know how to make it run at 2, but not 2:30.
6 Answers
...
Format / Suppress Scientific Notation from Python Pandas Aggregation Results
...float_format', lambda x: '%.3f' % x)
In [28]: Series(np.random.randn(3))*1000000000
Out[28]:
0 -757322420.605
1 -1436160588.997
2 -1235116117.064
dtype: float64
I'm not sure if that's the preferred way to do this, but it works.
Converting numbers to strings purely for aesthetic purposes ...
In where shall I use isset() and !empty()
...ty
FTA:
"isset() checks if a variable has a
value including (False, 0 or empty
string), but not NULL. Returns TRUE
if var exists; FALSE otherwise.
On the other hand the empty() function
checks if the variable has an empty
value empty string, 0, NULL or
False. Returns FALSE if v...
Does a break statement break from a switch/select?
...
201
Break statements, The Go Programming Language Specification.
A "break" statement termin...
Random date in C#
...
edited Jan 13 '16 at 23:10
Jeremy Thompson
49.5k1919 gold badges141141 silver badges245245 bronze badges
...
Is it safe to use -1 to set all bits to true?
...
20 Answers
20
Active
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How to install Java SDK on CentOS?
...n you read this, the lastest available version may be different.
java-1.7.0-openjdk.x86_64
The above package alone will only install JRE. To also install javac and JDK, the following command will do the trick:
$ yum install java-1.7.0-openjdk*
These packages will be installing (as well as thei...
Merge Images Side by Side(Horizontally)
I have five images of sizes: 600x30, 600x30, 600x30, 600x30, 810x30. Their names are: 0.png, 1.png, 2.png, 3.png, 4.png, respectively.
...
Pandas dataframe get first row of each group
...column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6 first
6 7 fourth
To get n first records, you can use head():
>>> df.groupby('id').head(2).reset_index(drop=True)
id value
0 ...