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How to do multiple arguments to map function where one remains the same in python?
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One option is a list comprehension:
[add(x, 2) for x in [1, 2, 3]]
More options:
a = [1, 2, ...
Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...o 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...
How do I find the duplicates in a list and create another list with them?
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In Matplotlib, what does the argument mean in fig.add_subplot(111)?
... a single integer. For example, "111" means "1x1 grid, first subplot" and "234" means "2x3 grid, 4th subplot".
Alternative form for add_subplot(111) is add_subplot(1, 1, 1).
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How can building a heap be O(n) time complexity?
...ap. The work required for the siftDown approach is given by the sum
(0 * n/2) + (1 * n/4) + (2 * n/8) + ... + (h * 1).
Each term in the sum has the maximum distance a node at the given height will have to move (zero for the bottom layer, h for the root) multiplied by the number of nodes at that hei...
Split delimited strings in a column and insert as new rows [duplicate]
...is another way of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split = ",")
data.frame(V1 = rep(df$V1, sapply(s, length))...
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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Remove all the elements that occur in one list from another
Let's say I have two lists, l1 and l2 . I want to perform l1 - l2 , which returns all elements of l1 not in l2 .
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