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What is “Orthogonality”?
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255
Orthogonality is the property that means "Changing A does not change B". An example of an ort...
Combine Date and Time columns using python pandas
...y to_datetime:
In [11]: df['Date'] + ' ' + df['Time']
Out[11]:
0 01-06-2013 23:00:00
1 02-06-2013 01:00:00
2 02-06-2013 21:00:00
3 02-06-2013 22:00:00
4 02-06-2013 23:00:00
5 03-06-2013 01:00:00
6 03-06-2013 21:00:00
7 03-06-2013 22:00:00
8 03-06-2013 23:00:00
9 04-06-...
Relative frequencies / proportions with dplyr
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295
Try this:
mtcars %>%
group_by(am, gear) %>%
summarise(n = n()) %>%
mutate(freq...
Why is TypedReference behind the scenes? It's so fast and safe… almost magical!
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42
Short answer: portability.
While __arglist, __makeref, and __refvalue are language extensions an...
Generator Expressions vs. List Comprehension
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294
John's answer is good (that list comprehensions are better when you want to iterate over somet...
What does it mean by select 1 from table?
... dwell)).
SELECT * FROM TABLE1 T1 WHERE EXISTS (
SELECT 1 FROM TABLE2 T2 WHERE T1.ID= T2.ID
);
Basically, the above will return everything from table 1 which has a corresponding ID from table 2. (This is a contrived example, obviously, but I believe it conveys the idea. Personally, I would...
How to configure Visual Studio to use Beyond Compare
...the proper path for your machine, including version number)
Arguments: %1 %2 /title1=%6 /title2=%7
If using Beyond Compare Professional (3-way Merge):
Extension: .*
Operation: Merge
Command: C:\Program Files\Beyond Compare 3\BComp.exe (replace with the proper path for your machine, including ver...
String formatting named parameters?
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In Python 2.6+ and Python 3, you might choose to use the newer string formatting method.
print('<a href="{0}">{0}</a>'.format(my_url))
which saves you from repeating the argument, or
print('<a href="{url}">{url}&l...
Angular.js directive dynamic templateURL
...
edited Feb 18 '14 at 10:02
answered Feb 17 '14 at 17:44
pg...