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Add new row to dataframe, at specific row-index, not appended?
...ds the (often slow) rbind call:
existingDF <- as.data.frame(matrix(seq(20),nrow=5,ncol=4))
r <- 3
newrow <- seq(4)
insertRow <- function(existingDF, newrow, r) {
existingDF[seq(r+1,nrow(existingDF)+1),] <- existingDF[seq(r,nrow(existingDF)),]
existingDF[r,] <- newrow
existin...
Common xlabel/ylabel for matplotlib subplots
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218
This looks like what you actually want. It applies the same approach of this answer to your sp...
What is the behavior of integer division?
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edited Jun 30 '18 at 17:32
cmaher
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answered Aug 3...
Passing parameters in rails redirect_to
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edited Oct 21 '15 at 14:19
bmalets
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git: Show index diff in commit message as comment
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answered Jan 20 '11 at 17:09
Alan Haggai AlaviAlan Haggai Alavi
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How to delete an element from an array in C#
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342
If you want to remove all instances of 4 without needing to know the index:
LINQ: (.NET Framewo...
Should I use a data.frame or a matrix?
...e the choice.
Also:
Matrices are more memory efficient:
m = matrix(1:4, 2, 2)
d = as.data.frame(m)
object.size(m)
# 216 bytes
object.size(d)
# 792 bytes
Matrices are a necessity if you plan to do any linear algebra-type of operations.
Data frames are more convenient if you frequently refer to ...
PostgreSQL - max number of parameters in “IN” clause?
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Jordan S. JonesJordan S. Jones
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add a ...
How to insert a character in a string at a certain position?
...igit value. I want to display it as a String with a decimal point (.) at 2 digits from the end of int . I wanted to use a float but was suggested to use String for a better display output (instead of 1234.5 will be 1234.50 ). Therefore, I need a function that will take an int as paramete...