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How can I remove a key and its value from an associative array?
...use unset:
unset($array['key-here']);
Example:
$array = array("key1" => "value1", "key2" => "value2");
print_r($array);
unset($array['key1']);
print_r($array);
unset($array['key2']);
print_r($array);
Output:
Array
(
[key1] => value1
[key2] => value2
)
Array
(
[key2] ...
Can Eclipse refresh resources automatically?
... the filesystem periodically.
From 3.7 there's a new preference Settings > General > Workspace > Refresh On Access (aka Lightweight Refresh). This preference causes Eclipse to automatically refresh resources when it discovers that they're 'out-of-sync'. When opening, reading or searching...
Editing legend (text) labels in ggplot
...ur data:
# transforming the data from wide to long
library(reshape2)
dfm <- melt(df, id = "TY")
# creating a scatterplot
ggplot(data = dfm, aes(x = TY, y = value, color = variable)) +
geom_point(size=5) +
labs(title = "Temperatures\n", x = "TY [°C]", y = "Txxx", color = "Legend Title\n") ...
What is the maximum float in Python?
...
For float have a look at sys.float_info:
>>> import sys
>>> sys.float_info
sys.floatinfo(max=1.7976931348623157e+308, max_exp=1024, max_10_exp=308, min=2.2
250738585072014e-308, min_exp=-1021, min_10_exp=-307, dig=15, mant_dig=53, epsil
on=2.2204460...
Cartesian product of x and y array points into single array of 2D points
...
>>> numpy.transpose([numpy.tile(x, len(y)), numpy.repeat(y, len(x))])
array([[1, 4],
[2, 4],
[3, 4],
[1, 5],
[2, 5],
[3, 5]])
See Using numpy to build an array of all combinations ...
How to empty (“truncate”) a file on linux that already exists and is protected in someway?
...set. The error looks like it's from csh, so you would do:
cat /dev/null >! file
If I'm wrong and you are using bash, you should do:
cat /dev/null >| file
in bash, you can also shorten that to:
>| file
share...
Android activity life cycle - what are all these methods for?
...be created until A's onPause() returns, so be sure to not
do anything lengthy here.
onStop():
Called when you are no longer visible to the user. You will next
receive either onRestart(), onDestroy(), or nothing, depending on
later user activity.
Note that this method may never be calle...
Import Maven dependencies in IntelliJ IDEA
... will be loaded automatically.
You can enable such feature going to File > Settings > Maven > Importing, there is a checkbox that says "Import Maven projects automatically".
If that doesn't help, then I would suggest to make a full clean-up and start again:
Close your project window (an...
Random hash in Python
...d4().hex
UUID4 gives you a random unique identifier that has the same length as a md5 sum. Hex will represent is as an hex string instead of returning a uuid object.
http://docs.python.org/2/library/uuid.html
share
...
Finding the number of days between two dates
...
If you're using PHP 5.3 >, this is by far the most accurate way of calculating the difference:
$earlier = new DateTime("2010-07-06");
$later = new DateTime("2010-07-09");
$diff = $later->diff($earlier)->format("%a");
...