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how do I insert a column at a specific column index in pandas?

... the beginning df.insert(loc, column, value) df = pd.DataFrame({'B': [1, 2, 3], 'C': [4, 5, 6]}) df Out: B C 0 1 4 1 2 5 2 3 6 idx = 0 new_col = [7, 8, 9] # can be a list, a Series, an array or a scalar df.insert(loc=idx, column='A', value=new_col) df Out: A B C 0 7 1 ...
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Is there an R function for finding the index of an element in a vector?

... that is equal to x . I know that one way to do this is: which(x == v)[[1]] , but that seems excessively inefficient. Is there a more direct way to do it? ...
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How to find the installed pandas version

...sion__: In [76]: 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:...
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Replacing NAs with latest non-NA value

... 18 Answers 18 Active ...
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How to convert 1 to true or 0 to false upon model fetch

...th true or false into a boolean/tinyint field in the database, which uses 1 or 0 . 4 Answers ...
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How do you rotate a two dimensional array?

... 1 2 3 Next 144 ...
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How exactly does tail recursion work?

... 169 The compiler is simply able to transform this int fac_times (int n, int acc) { if (n == 0...
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Set Colorbar Range in matplotlib

... 182 Using vmin and vmax forces the range for the colors. Here's an example: import matplotlib ...
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Reduce, fold or scan (Left/Right)?

...hrough the first argument res of our binary operator minus: val xs = List(1, 2, 3, 4) def minus(res: Int, x: Int) = { println(s"op: $res - $x = ${res - x}") res - x } xs.reduceLeft(minus) // op: 1 - 2 = -1 // op: -1 - 3 = -4 // de-cumulates value -1 in *first* operator arg `res` // op: -4 - ...
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How to form tuple column from two columns in Pandas

... | edited Nov 7 '16 at 16:58 answered Apr 17 '13 at 19:24 ...