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deleting rows in numpy array
...thod.
Suppose I have the following array x:
x = array([[1,2,3],
[4,5,6],
[7,8,9]])
To delete the first row, do this:
x = numpy.delete(x, (0), axis=0)
To delete the third column, do this:
x = numpy.delete(x,(2), axis=1)
So you could find the indices of the rows which have a ...
How to iterate for loop in reverse order in swift?
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14 Answers
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Why does 0.ToString(“#.##”) return an empty string instead of 0.00 or at least 0?
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edited Jan 31 '12 at 18:14
answered Jan 25 '12 at 11:04
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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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What is the fastest integer division supporting division by zero no matter what the result is?
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4 Answers
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SQL Logic Operator Precedence: And and Or
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4 Answers
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How to find the installed pandas version
...]: import pandas as pd
In [77]: pd.__version__
Out[77]: '0.12.0-933-g281dc4e'
Pandas also provides a utility function, pd.show_versions(), which reports the version of its dependencies as well:
In [53]: pd.show_versions(as_json=False)
INSTALLED VERSIONS
------------------
commit: None
python: 2...
What does this square bracket and parenthesis bracket notation mean [first1,last1)?
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Numbering rows within groups in a data frame
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284
Use ave, ddply, dplyr or data.table:
df$num <- ave(df$val, df$cat, FUN = seq_along)
or:
l...
Custom numeric format string to always display the sign
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edited May 24 '16 at 21:50
Craig
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