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pandas GroupBy columns with NaN (missing) values
...cient topic, if someone still stumbles over this--another workaround is to convert via .astype(str) to string before grouping. That will conserve the NaN's.
df = pd.DataFrame({'a': ['1', '2', '3'], 'b': ['4', np.NaN, '6']})
df['b'] = df['b'].astype(str)
df.groupby(['b']).sum()
a
b
4 1
6 ...
Setting the correct encoding when piping stdout in Python
..."åäö".encode('utf-8')
Another didactic example is a Python program to convert between ISO-8859-1 and UTF-8, making everything uppercase in between.
import sys
for line in sys.stdin:
# Decode what you receive:
line = line.decode('iso8859-1')
# Work with Unicode internally:
line...
How to check Google Play services version?
...y services version (which is installed in user's device). Is it possible ? And if yes, how can I do that? I searched Google but I could not find anything!
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Confused about __str__ on list in Python [duplicate]
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Python has two different ways to convert an object to a string: str() and repr(). Printing an object uses str(); printing a list containing an object uses str() for the list itself, but the implementation of list.__str__() calls repr() for the individual it...
How do you set the max number of characters for an EditText in Android?
...LengthFilter(MAX_NUM) });
Via xml:
<EditText
android:maxLength="@integer/max_edittext_length"
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python max function using 'key' and lambda expression
I come from OOP background and trying to learn python.
I am using the max function which uses a lambda expression to return the instance of type Player having maximum totalScore among the list players .
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Why does .NET foreach loop throw NullRefException when collection is null?
...the answer might be obvious to some people, it is not obvious to everyone, and providing the hint that looking at the IL will tell you what the compiler is doing, helps people fish for themselves in the future.
– Robaticus
May 10 '17 at 23:36
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How to throw an exception in C?
...tion (or other notification error form the CPU if there is)(How processor handles the case of division by zero).
Exceptions are defined in C++ and other languages though. Exception handling in C++ is specified in the C++ standard "S.15 Exception handling", there is no equivalent section in the C st...
Precise Financial Calculation in JavaScript. What Are the Gotchas?
... that the JavaScript lexer reads the string "0.1" from the source and then converts it to a binary floating point and then you already did an unintended rounding. The problem is about representation (binary vs decimal) not about precision.
– mgd
Nov 20 '15 at 1...
What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?
...pedef :ed primitive data types is to abstract the low-level representation and make it easier to comprehend ( uint64_t instead of long long type, which is 8 bytes).
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