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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 ...
How to hash a string into 8 digits?
...
96
Raymond's answer is great for python2 (though, you don't need the abs() nor the parens around 1...
Can't open config file: /usr/local/ssl/openssl.cnf on Windows [duplicate]
I have installed OpenSSL 64. I want to use a certificate for my nodejs https server. I ran the following command:
7 Answers...
Is there a range class in C++11 for use with range based for loops?
...icol Bolas
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3
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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...
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...
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for MinGW-w64 toolchains) as a recent fork of Cygwin which tracks the latest Cygwin closely so that it doesn't end up out of date.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...
Calculate distance between two latitude-longitude points? (Haversine formula)
...phere)? The original question asked for distance on between points on a WGS84 globe. Not sure how much error creeps in by using a perfect sphere, but I suspect it can be quite a lot depending on where the points are on the globe, thus the distinction is worth bearing in mind.
–...
How to get the number of characters in a std::string?
...98cd 89cc 9f67 cc92 cd9d cd85 cd95 cd94 .....g..........
00000040: cca4 cd96 cc9f 6fcc 90cd afcc 9acc 85cd ......o.........
00000050: aacc 86cd a3cc a1cc b5cc a1cc bccd 9a ...............
50 codepoints
LATIN CAPITAL LETTER Z
COMBINING LEFT ANGLE BELOW
COMBINING DOUBLE LOW LINE
COMBINING INVE...