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nil detection in Go
... I think this is wrong, as it is always false: play.golang.org/p/g-MdbEbnyNx
– Madeo
Oct 16 '19 at 0:29
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Is there an R function for finding the index of an element in a vector?
In R, I have an element x and a vector v . I want to find the first index of an element in v that is equal to x . I know that one way to do this is: which(x == v)[[1]] , but that seems excessively inefficient. Is there a more direct way to do it?
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How can I check if a file exists in Perl?
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Test whether something exists at given path using the -e file-test operator.
print "$base_path exists!\n" if -e $base_path;
However, this test is probably broader than you intend. The code above will generate output if a plain file exists at that...
How to make execution pause, sleep, wait for X seconds in R?
...ction, but ?sleep references a data set. And ?pause and ?wait don't exist.
2 Answers
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Why does integer division in C# return an integer and not a float?
...ing point number you would be forced to round the result every time. One example off of the top of my head is changing the base of a number. Calculating each digit involves the integer division of a number along with the remainder, rather than the floating point division of the number.
Because of...
Draw multi-line text to Canvas
A hopefully quick question, but I can't seem to find any examples... I'd like to write multi-line text to a custom View via a Canvas , and in onDraw() I have:
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SVG: text inside rect
I want to display some text inside SVG rect . Is it possible?
5 Answers
5
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How can I check for NaN values?
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math.isnan(x)
Return True if x is a NaN (not a number), and False otherwise.
>>> import math
>>> x = float('nan')
>>> math.isnan(x)
True
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How do I prevent 'git diff' from using a pager?
...IT_PAGER=cat git diff
# Tells 'less' not to paginate if less than a page
export LESS="-F -X $LESS"
# ...then Git as usual
git diff
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Remove grid, background color, and top and right borders from ggplot2
.... The bug mentioned below in the original post remains (I think). But the axis line is drawn under the panel. Therefore, remove both the panel.border and panel.background to see the axis lines.
library(ggplot2)
a <- seq(1,20)
b <- a^0.25
df <- as.data.frame(cbind(a,b))
ggplot(df, aes(x = ...