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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
I have a dataframe with ~300K rows and ~40 columns.
I want to find out if any rows contain null values - and put these 'null'-rows into a separate dataframe so that I could explore them easily.
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Truncate Two decimal places without rounding
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value = Math.Truncate(100 * value) / 100;
Beware that fractions like these cannot be accurately represented in floating point.
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improve t...
Looping in a spiral
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Here's my solution (in Python):
def spiral(X, Y):
x = y = 0
dx = 0
dy = -1
for i in range(max(X, Y)**2):
if (-X/2 < x <= X/2) and (-Y/2 < y <= Y/2):
print (x, y)
# DO STUFF...
if x == y or (x < 0 and x == -y) or (x &...
How to change the output color of echo in Linux
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30 Answers
30
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Use CSS3 transitions with gradient backgrounds
...been some browser releases that supported transitions on gradients (e.g IE10. I tested gradient transitions in 2016 in IE and they seemed to work at the time, but my test code no longer works.)
Update: October 2018
Gradient transitions with un-prefixed new syntax [e.g. radial-gradient(...)]now conf...
Fast permutation -> number -> permutation mapping algorithms
...ake of an example, let's say, 7 elements, 1234567. I know there are 7! = 5040 permutations possible of these 7 elements.
1...
Convert floats to ints in Pandas?
...nge(5), columns=['a'])
df.a = df.a.astype(float)
df
Out[33]:
a
0 0.0000000
1 1.0000000
2 2.0000000
3 3.0000000
4 4.0000000
pd.options.display.float_format = '{:,.0f}'.format
df
Out[35]:
a
0 0
1 1
2 2
3 3
4 4
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Apply pandas function to column to create multiple new columns?
...,
left_index=True, right_index=True)
textcol feature1 feature2
0 0.772692 1.772692 -0.227308
1 0.857210 1.857210 -0.142790
2 0.065639 1.065639 -0.934361
3 0.819160 1.819160 -0.180840
4 0.088212 1.088212 -0.911788
EDIT:
Please be aware of the huge memory consumption and low sp...
Multiple linear regression in Python
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102
sklearn.linear_model.LinearRegression will do it:
from sklearn import linear_model
clf = linea...
What are the differences between json and simplejson Python modules?
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wim
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answered Apr 3 '09 at 6:59
Devin JeanpierreDe...