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Append values to a set in Python
...to add elements from tuples, sets, lists or frozen-sets
a.update([3,4])
>> print(a)
{1, 2, 3, 4}
If you want to add a tuple or frozen-set itself, use add
a.add((5, 6))
>> print(a)
{1, 2, 3, 4, (5, 6)}
Note: Since set elements must be hashable, and lists are considered mutable, yo...
How to find and turn on USB debugging mode on Nexus 4
...an now enable/disable it whenever you desire by going to
“Settings” -> “Developer Options” -> “Debugging” ->” USB debugging”.
CONCLUSION
That was easy. The best part is you only have to do the tap-build-number-seven-times once. After you do it once, USB debugging has been...
Naming of enums in Java: Singular or Plural?
...n general) should be singular. The thinking is that you're not selecting multiple Protocols, but rather one Protocol of the possible choices in the list of values.
Note the absence of plurals: http://docs.oracle.com/javase/tutorial/java/javaOO/enum.html
...
numpy: most efficient frequency counts for unique values in an array
...in the original answer is deprecated, we should use the new way instead:
>>> import numpy as np
>>> x = [1,1,1,2,2,2,5,25,1,1]
>>> np.array(np.unique(x, return_counts=True)).T
array([[ 1, 5],
[ 2, 3],
[ 5, 1],
[25, 1]])
Origina...
Formatting “yesterday's” date in python
...
Use datetime.timedelta()
>>> from datetime import date, timedelta
>>> yesterday = date.today() - timedelta(days=1)
>>> yesterday.strftime('%m%d%y')
'110909'
...
Eclipse does not highlight matching variables
...
Try:
window > preferences > java > editor > mark occurrences
Select all options available there.
Also go to:
Preferences > General > Editors > Text Editors > Annotations
Compare the settings for 'Occurrences...
Why does += behave unexpectedly on lists?
...create a new object and assign it to a. They are not the same operation!
>>> a1 = a2 = [1, 2]
>>> b1 = b2 = [1, 2]
>>> a1 += [3] # Uses __iadd__, modifies a1 in-place
>>> b1 = b1 + [3] # Uses __add__, creates new list, assigns it to b1
>>> ...
How to get a vertical geom_vline to an x-axis of class date?
...ield[120]), linetype=4)
A simple test example:
library("ggplot2")
tmp <- data.frame(x=rep(seq(as.Date(0, origin="1970-01-01"),
length=36, by="1 month"), 2),
y=rnorm(72),
category=gl(2,36))
p <- ggplot(tmp, aes(x, y, colour=ca...
get list of pandas dataframe columns based on data type
...
If you want a list of columns of a certain type, you can use groupby:
>>> df = pd.DataFrame([[1, 2.3456, 'c', 'd', 78]], columns=list("ABCDE"))
>>> df
A B C D E
0 1 2.3456 c d 78
[1 rows x 5 columns]
>>> df.dtypes
A int64
B float64
C obje...
Representing graphs (data structure) in Python
...ind_shortest_path and other methods.
Let's see this in action though...
>>> connections = [('A', 'B'), ('B', 'C'), ('B', 'D'),
('C', 'D'), ('E', 'F'), ('F', 'C')]
>>> g = Graph(connections, directed=True)
>>> pretty_print = pprint.PrettyPrinter()
>&...