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How to make an app's background image repeat
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430
Ok, here's what I've got in my app. It includes a hack to prevent ListViews from going black wh...
Checking images for similarity with OpenCV
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This is a huge topic, with answers from 3 lines of code to entire research magazines.
I will outline the most common such techniques and their results.
Comparing histograms
One of the simplest & fastest methods. Proposed decades ago as a means to find picture s...
Convert columns to string in Pandas
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355
One way to convert to string is to use astype:
total_rows['ColumnID'] = total_rows['ColumnID'...
How to get last items of a list in Python?
...re's an example using the python CLI interpreter:
>>> a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a[-9:]
[4, 5, 6, 7, 8, 9, 10, 11, 12]
the important line is a[-9:]
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How to get thread id from a thread pool?
...t which one of those 5 threads executes my task (something like "thread #3 of 5 is doing this task")?
6 Answers
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Class with Object as a parameter
...es Table to be a new-style class (as opposed to "classic" class).
In Python3 all classes are new-style classes, so this is no longer necessary.
New style classes have a few special attributes that classic classes lack.
class Classic: pass
class NewStyle(object): pass
print(dir(Classic))
# ['__doc...
Array initializing in Scala
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143
scala> val arr = Array("Hello","World")
arr: Array[java.lang.String] = Array(Hello, World)
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Only read selected columns
... header = TRUE)
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
Change "integer" to one of the accepted types as detailed in ?read.table depending on the real type of data.
data.txt looks like this:
$ cat data.tx...
Convert integer to string Jinja
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edited Apr 3 '15 at 13:58
Ajoy
1,81433 gold badges2727 silver badges5353 bronze badges
an...
How does tuple comparison work in Python?
...ist, the shorter collection is ordered first (for example, [1,2] < [1,2,3] is true).
If not equal, the sequences are ordered the same as their first differing elements. For example, cmp([1,2,x], [1,2,y]) returns the same as cmp(x,y). If the corresponding element does not exist, the shorter sequ...