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Writing Unicode text to a text file?
I'm pulling data out of a Google doc, processing it, and writing it to a file (that eventually I will paste into a Wordpress page).
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How should one use std::optional?
I'm reading the documentation of std::experimental::optional and I have a good idea about what it does, but I don't understand when I should use it or how I should use it. The site doesn't contain any examples as of yet which leaves it harder for me to grasp the true concept of this object. When...
How to merge 2 List and removing duplicate values from it in C#
I have two lists List that I need to combine in third list and remove duplicate values from that lists
5 Answers
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Convert columns to string in Pandas
...e looking for the to_json function, which will convert keys to valid json (and therefore your keys to strings):
In [11]: df = pd.DataFrame([['A', 2], ['A', 4], ['B', 6]])
In [12]: df.to_json()
Out[12]: '{"0":{"0":"A","1":"A","2":"B"},"1":{"0":2,"1":4,"2":6}}'
In [13]: df[0].to_json()
Out[13]: '{"...
If vs. Switch Speed
...es a hash table to dispatch these. The hash table uses the strings as keys and delegates to the case codes as values.
This has asymptotic better runtime than lots of chained if tests and is actually faster even for relatively few strings.
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How do I find out which keystore was used to sign an app?
I have an app which is signed and several keystore files. I'd like to update the app, so I need to find out which one of keys was used.
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Iterating through a range of dates in Python
...e in (start_date + timedelta(n) for n in range(day_count)):
print ...
And no list gets stored, only one generator is iterated over. Also the "if" in the generator seems to be unnecessary.
After all, a linear sequence should only require one iterator, not two.
Update after discussion with John M...
How to compare two dates?
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Use the datetime method and the operator < and its kin.
>>> from datetime import datetime, timedelta
>>> past = datetime.now() - timedelta(days=1)
>>> present = datetime.now()
>>> past < present
True
>&g...
What's the syntax for mod in java
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Careful with the terms mod and modular because n (mod m) IS ALWAYS >= 0 but not n % m. n % m is in the range > -m and < m. Although Java has a remainder operator for int and long types, it has no modulus function or operator. I.e., -12 % 10 = ...
Select first row in each GROUP BY group?
... BY p.customer) y ON y.customer = x.customer
AND y.max_total = x.total
GROUP BY x.customer, x.total
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