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Applying a function to every row of a table using dplyr?
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As of dplyr 0.2 (I think) rowwise() is implemented, so the answer to this problem becomes:
ir...
Ruby Bundle Symbol not found: _SSLv2_client_method (LoadError)
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287
I just fixed a similar issue on my system. You need to rebuild your install of Ruby 2.1.2 and ...
How to convert float to int with Java
...ted May 7 '15 at 18:03
user719662
answered Aug 18 '09 at 17:41
tw39124tw39124
8,00722 ...
Summarizing multiple columns with dplyr? [duplicate]
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260
The dplyr package contains summarise_all for this aim:
library(dplyr)
df %>% group_by(grp) ...
How to select the row with the maximum value in each group
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Here's a data.table solution:
require(data.table) ## 1.9.2
group <- as.data.table(group)
If you want to keep all the entries corresponding to max values of pt within each group:
group[group[, .I[pt == max(pt)], by=Subject]$V1]
# Subject pt Event
# 1: 1 5 2
# 2: ...
Remove duplicate elements from array in Ruby
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727
array = array.uniq
uniq removes all duplicate elements and retains all unique elements in the...
How to count the frequency of the elements in an unordered list?
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Formatting a number with exactly two decimals in JavaScript
...ounds my numbers to two decimal places. But I get numbers like this: 10.8, 2.4, etc. These are not my idea of two decimal places so how I can improve the following?
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Numpy array dimensions
... ndarray.shape
Tuple of array dimensions.
Thus:
>>> a.shape
(2, 2)
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Computational complexity of Fibonacci Sequence
...b(n) as sum of time to calculate Fib(n-1) plus the time to calculate Fib(n-2) plus the time to add them together (O(1)). This is assuming that repeated evaluations of the same Fib(n) take the same time - i.e. no memoization is use.
T(n<=1) = O(1)
T(n) = T(n-1) + T(n-2) + O(1)
You solve this r...