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How do I get the row count of a pandas DataFrame?
...eturn non-NaN counts for each column:
df.count()
A 5
B 3
dtype: int64
For Series, use Series.count to similar effect:
s.count()
# 3
Group-wise Row Count: GroupBy.size
For DataFrames, use DataFrameGroupBy.size to count the number of rows per group.
df.groupby('A').size()
A
a 2
b ...
Java: using switch statement with enum under subclass
...ecause it is clearer on what the issue is.
– joaorodr84
Sep 30 '19 at 22:00
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Resize svg when window is resized in d3.js
...
Rúnar Berg
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answered Sep 22 '14 at 15:55
cminatticminatti
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Get unique values from a list in python [duplicate]
...
96
A Python list:
>>> a = ['a', 'b', 'c', 'd', 'b']
To get unique items, just transfor...
Why does installing Nokogiri on Mac OS fail with libiconv is missing?
...or unsupported file format which is not the architecture being linked (x86_64) for architecture x86_64
Uhh, what? After a lot of googling, I came across this miracle post: http://www.refresherate.com/2010/01/08/fixing-ld-warning-in-usrlocalliblibz-dylib-file-is-not-of-required-architecture/
Appar...
Which is faster: while(1) or while(2)?
... call __main
.L2:
jmp .L2
.seh_endproc
.ident "GCC: (tdm64-2) 4.8.1"
With -O1:
.file "main.c"
.intel_syntax noprefix
.def __main; .scl 2; .type 32; .endef
.text
.globl main
.def main; .scl 2; .type 32; .endef
.seh_proc main
mai...
How do I use the new computeIfAbsent function?
...
96
Suppose you have the following code:
import java.util.Map;
import java.util.concurrent.Concurr...
Custom Cell Row Height setting in storyboard is not responding
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84
If you use UITableViewController, implement this method:
- (CGFloat)tableView:(UITableView *)t...
Why are floating point numbers inaccurate?
...the Data
First, a few functions to see the components that make a 32- and 64-bit float. Gloss over these if you only care about the output (example in Python):
def float_to_bin_parts(number, bits=64):
if bits == 32: # single precision
int_pack = 'I'
float_pack ...
How are msys, msys2, and msysgit related to each other?
...Pavlov of the mingw-builds team (who are the official packagers for MinGW-w64 toolchains) as a recent fork of Cygwin which tracks the latest Cygwin closely so that it doesn't end up out of date. Alexey forward ported the old MSYS patches and added some of his own.
As well as providing the necessary...