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Pandas dataframe get first row of each group
I have a pandas DataFrame like following.
5 Answers
5
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Python __str__ versus __unicode__
...ns. Generally, you should put all your string formatting in __unicode__(), and create a stub __str__() method:
def __str__(self):
return unicode(self).encode('utf-8')
In 3.0, str contains characters, so the same methods are named __bytes__() and __str__(). These behave as expected.
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Can I list-initialize a vector of move-only type?
...gspot.com/2013/09/…). The idea is to determine lvalue/rvalue at run-time and then call move or copy-construction. in<T> will detect rvalue/lvalue even though the standard interface provided by initializer_list is const reference.
– Sumant
Sep 24 '13 at ...
What's the idiomatic syntax for prepending to a short python list?
... explanation for the missing list.prepend() . Assuming my list is short and performance concerns are negligible, is
4 A...
Increase distance between text and title on the y-axis
...= argument of element_text() to change the distance between the axis title and the numbers. Set the values of the margin on top, right, bottom, and left side of the element.
ggplot(mpg, aes(cty, hwy)) + geom_point()+
theme(axis.title.y = element_text(margin = margin(t = 0, r = 20, b = 0, l = 0)))...
In Python, how to display current time in readable format
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First the quick and dirty way, and second the precise way (recognizing daylight's savings or not).
import time
time.ctime() # 'Mon Oct 18 13:35:29 2010'
time.strftime('%l:%M%p %Z on %b %d, %Y') # ' 1:36PM EDT on Oct 18, 2010'
time.strftime(...
How to read keyboard-input?
...f you use Python 2
input('Enter your input:') # If you use Python 3
and if you want to have a numeric value
just convert it:
try:
mode=int(raw_input('Input:'))
except ValueError:
print "Not a number"
share...
Which is faster in Python: x**.5 or math.sqrt(x)?
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I've now run it 3 times on codepad.org and all three times a() was much faster than b().
– Jeremy Ruten
Nov 29 '08 at 1:38
13
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Will Dispose() be called in a using statement with a null object?
... Note that even if your variable is null, the using block is executed, and if you reference your variable inside the using block without first null-checking it, you WILL get NullReferenceException. To prevent misinterpretation, this answer should state: "Yes, Dispose() is only called on non-null...
Releasing memory in Python
...llocator. The int type maintains a freelist with its own allocated memory, and clearing it requires calling PyInt_ClearFreeList(). This can be called indirectly by doing a full gc.collect.
Try it like this, and tell me what you get. Here's the link for psutil.Process.memory_info.
import os
import...