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How to solve PHP error 'Notice: Array to string conversion in…'
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112
When you have many HTML inputs named C[] what you get in the POST array on the other end is an a...
Shortest distance between a point and a line segment
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52 Answers
52
Active
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Setting Vim whitespace preferences by filetype
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245
there are many ways, but here's a simple, easy to understand way. add these lines to your ~/.v...
Maven: missing net.sf.json-lib
...-lib in the central repository . Copy-pasted the dependency (with version 2.3), and then when I build I get this error:
4 ...
How can I autoformat/indent C code in vim?
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answered Mar 1 '10 at 12:52
Amir RachumAmir Rachum
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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...
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...
The most efficient way to implement an integer based power function pow(int, int)
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edited Apr 4 '18 at 7:26
John Zwinck
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an...
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 ...
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...