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Why is it slower to iterate over a small string than a small list?
...n a list of small single character strings. Any explanation? It's almost 1.35 times as much time.
3 Answers
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cartesian product in pandas
...import DataFrame, merge
df1 = DataFrame({'key':[1,1], 'col1':[1,2],'col2':[3,4]})
df2 = DataFrame({'key':[1,1], 'col3':[5,6]})
merge(df1, df2,on='key')[['col1', 'col2', 'col3']]
Output:
col1 col2 col3
0 1 3 5
1 1 3 6
2 2 4 5
3 2 4 6
See here...
Convert pandas dataframe to NumPy array
...50
cs95
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answered May 5 '16 at 5:29
User456898User...
Matplotlib scatter plot with different text at each data point
... could use annotate() while iterating over the values in n.
y = [2.56422, 3.77284, 3.52623, 3.51468, 3.02199]
z = [0.15, 0.3, 0.45, 0.6, 0.75]
n = [58, 651, 393, 203, 123]
fig, ax = plt.subplots()
ax.scatter(z, y)
for i, txt in enumerate(n):
ax.annotate(txt, (z[i], y[i]))
There are a lot of...
Get operating system info
...t 10/i' => 'Windows 10',
'/windows nt 6.3/i' => 'Windows 8.1',
'/windows nt 6.2/i' => 'Windows 8',
'/windows nt 6.1/i' => 'Windows 7',
'/windows nt 6.0/i' =>...
Find MongoDB records where array field is not empty
...
873
If you also have documents that don't have the key, you can use:
ME.find({ pictures: { $exists:...
How to convert floats to human-readable fractions?
Let's say we have 0.33 , we need to output 1/3 .
If we have 0.4 , we need to output 2/5 .
26 Answers
...
Adding a column to a data.frame
...cording to column 1 ( h_no ) in that way that the first series of h_no 1,2,3,4 is class 1, the second series of h_no (1 to 7) is class 2 etc. such as indicated in the last column.
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Numbering rows within groups in a data frame
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answered Oct 16 '12 at 23:41
mnelmnel
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