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count the frequency that a value occurs in a dataframe column
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In [38]:
df['a'].value_counts()
Out[38]:
b 3
a 2
s 2
dtype: int64
If you wanted to add frequency back to the original dataframe use transform to return an aligned index:
In [41]:
df['freq'] = df.groupby('a')['a'].transform('count')
df
Out[41]:
a freq
0 a 2
1 b 3
2 s 2...
Update just one gem with bundler
...undle update
> ruby -v
ruby 2.6.5p114 (2019-10-01 revision 67812) [x86_64-darwin19]
> gem -v
3.0.3
> bundle -v
Bundler version 2.1.4
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How expensive is RTTI?
...runtime memory usage.
A quick experiment (using GCC 4.4.3 on Ubuntu 10.04 64-bit) shows that -fno-rtti actually increases the binary size of a simple test program by a few hundred bytes. This happens consistently across combinations of -g and -O3. I'm not sure why the size would increase; one possi...
Lua string to int
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In Lua 5.3, (64-bit default) integers are treated accordingly (lua.org/manual/5.3/manual.html): "A numeric constant with a fractional dot or an exponent denotes a float; otherwise it denotes an integer."
– Kevin Lee
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How to draw an empty plot?
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64
I suggest that someone needs to make empty plot in order to add some graphics on it later. So, ...
Format / Suppress Scientific Notation from Python Pandas Aggregation Results
...0000000
Out[28]:
0 -757322420.605
1 -1436160588.997
2 -1235116117.064
dtype: float64
I'm not sure if that's the preferred way to do this, but it works.
Converting numbers to strings purely for aesthetic purposes seems like a bad idea, but if you have a good reason, this is one way:
In [6...
Hiding the scroll bar on an HTML page
...: auto, but I'm not a fan of abusing width for visibility tweaks.
Firefox 64 now supports the experimental scrollbar-width property by default (63 requires a configuration flag to be set). To hide the scrollbar in Firefox 64:
#element {
scrollbar-width: none;
}
To see if your current browser...
What optimizations can GHC be expected to perform reliably?
...ckage integer-gmp mapped to integer-gmp-0.4.0.0-af3a28fdc4138858e0c7c5ecc2a64f43
wired-in package base mapped to base-4.5.1.0-6e4c9bdc36eeb9121f27ccbbcb62e3f3
wired-in package rts mapped to builtin_rts
wired-in package template-haskell mapped to template-haskell-2.7.0.0-2bd128e15c2d50997ec26a1eaf8b2...
Chain-calling parent initialisers in python [duplicate]
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dF.dF.
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Convert a CERT/PEM certificate to a PFX certificate
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FrancisFrancis
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