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How to get a substring of text?
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207
Use String#slice, also aliased as [].
a = "hello there"
a[1] #=> "e"
a[1...
How can I create a correlation matrix in R?
... between your matrix x and matrix y. Ex.:
set.seed(1)
x <- matrix(rnorm(20), nrow=5, ncol=4)
y <- matrix(rnorm(15), nrow=5, ncol=3)
COR <- cor(x,y)
COR
image(x=seq(dim(x)[2]), y=seq(dim(y)[2]), z=COR, xlab="x column", ylab="y column")
text(expand.grid(x=seq(dim(x)[2]), y=seq(dim(y)[2])), la...
Git commit date
...t=%ct <commit>
– xiaoweiz
Oct 20 '16 at 13:37
2
If you want another date format, you can us...
Referencing another schema in Mongoose
...ksweetnicksweet
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How do I rename all files to lowercase?
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answered Oct 16 '11 at 20:39
wjlwjl
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Do you need to use path.join in node.js?
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answered Feb 27 '14 at 20:59
dronusdronus
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format date with moment.js
...ponseDate = moment(formatDate).format('DD/MM/YYYY');
My output is "13/05/2014"
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Comment out text in R Markdown (Rmd file)
...hanks!
– HelloGoodbye
Sep 24 '19 at 20:41
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No “pull” in Git Gui?
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answered Nov 29 '18 at 20:38
Jaroslav KubošJaroslav Kuboš
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Selecting with complex criteria from pandas.DataFrame
... B C
0 9 40 300
1 9 70 700
2 5 70 900
3 8 80 900
4 7 50 200
5 9 30 900
6 2 80 700
7 2 80 400
8 5 80 300
9 7 70 800
We can apply column operations and get boolean Series objects:
>>> df["B"] > 50
0 False
1 True
2 True
3 True
4 False
5...