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How can I sort a dictionary by key?
What would be a nice way to go from {2:3, 1:89, 4:5, 3:0} to {1:89, 2:3, 3:0, 4:5} ?
I checked some posts but they all use the "sorted" operator that returns tuples.
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Applying a function to every row of a table using dplyr?
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edited Aug 6 '19 at 3:20
answered Jul 14 '14 at 0:20
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How do you match only valid roman numerals with a regular expression?
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330
You can use the following regex for this:
^M{0,4}(CM|CD|D?C{0,3})(XC|XL|L?X{0,3})(IX|IV|V?I{0...
Does assignment with a comma work?
Why does aaa = 1,2,3 work and set the value of aaa to 1 ?
4 Answers
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“ValueError: zero length field name in format” error in Python 3.0,3.1,3.2
I'm trying learn Python (3 to be more specific) and I'm getting this error:
3 Answers
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Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...similar questions scattered around this site.
tmp <- data.frame(x=gl(2,3, labels=letters[24:25]),
y=gl(3,1,6, labels=letters[1:3]),
z=c(1,2,3,3,3,2))
Using the tidyverse:
The new cool new way to do this is with pivot_wider from tidyr 1.0.0. It returns a d...
Using numpy to build an array of all combinations of two arrays
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131
In newer version of numpy (>1.8.x), numpy.meshgrid() provides a much faster implementation:
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Base64 length calculation?
...log2(64) = 6).
Therefore 4 chars are used to represent 4 * 6 = 24 bits = 3 bytes.
So you need 4*(n/3) chars to represent n bytes, and this needs to be rounded up to a multiple of 4.
The number of unused padding chars resulting from the rounding up to a multiple of 4 will obviously be 0, 1, 2 or...
What does axis in pandas mean?
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399
It specifies the axis along which the means are computed. By default axis=0. This is consisten...
How do I use floating-point division in bash?
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– Nahuel Fouilleul
Oct 4 '12 at 7:32
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