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How to write a cron that will run a script every day at midnight?
...how to use it on Ubuntu. Your crontab line will look something like this:
00 00 * * * ruby path/to/your/script.rb
(00 00 indicates midnight--0 minutes and 0 hours--and the *s mean every day of every month.)
Syntax:
mm hh dd mt wd command
mm minute 0-59
hh hour 0-23
dd day of month 1-...
str performance in python
...
105
'%s' % 100000 is evaluated by the compiler and is equivalent to a constant at run-time.
>&g...
What does |= (ior) do in Python?
...
Here we apply merge (|) and update (|=) to dicts:
>>> d1 = {"a": 0, "b": 1, "c": 2}
>>> d2 = {"c": 20, "d": 30}
>>> # Merge, |
>>> d1 | d2
{"a": 0, "b": 1, "c": 20, "d": 30}
>>> d1
{"a": 0, "b": 1, "c": 2}
>>> # Update, |=
>>> d1 |=...
How do I get Flask to run on port 80?
I have a Flask server running through port 5000, and it's fine. I can access it at http://example.com:5000
14 Answers
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How to create a density plot in matplotlib?
... [4.5]*3 + [5.5]*1 + [6.5]*8
density = gaussian_kde(data)
xs = np.linspace(0,8,200)
density.covariance_factor = lambda : .25
density._compute_covariance()
plt.plot(xs,density(xs))
plt.show()
I get
which is pretty close to what you are getting from R. What have I done? gaussian_kde uses a changa...
MySQL - Rows to Columns
...temvalue |
+--------+----------+-----------+
| 1 | A | 10 |
| 1 | B | 3 |
| 2 | A | 9 |
| 2 | C | 40 |
+--------+----------+-----------+
This will be our goal, the pretty pivot table:
select * from history_itemvalue_piv...
Shading a kernel density plot between two points.
...x(which(dens$x < q95))
with(dens, polygon(x=c(x[c(x1,x1:x2,x2)]), y= c(0, y[x1:x2], 0), col="gray"))
Output (added by JDL)
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Difference between Math.Floor() and Math.Truncate()
...|
edited May 23 '17 at 12:03
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111 silver badge
answered Aug 1 '08 at 12:26
...
How can I count the number of matches for a regex?
... following. (Starting from Java 9, there is a nicer solution)
int count = 0;
while (matcher.find())
count++;
Btw, matcher.groupCount() is something completely different.
Complete example:
import java.util.regex.*;
class Test {
public static void main(String[] args) {
String hel...
How to create GUID / UUID?
... be of the form "xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx", where x is one of [0-9, a-f] M is one of [1-5], and N is [8, 9, a, or b]
Use of a low-quality source of randomness (such as Math.random)
Thus, developers writing code for production environments are encouraged to use a rigorous, well-maintain...