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How to find the length of a string in R
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See ?nchar. For example:
> nchar("foo")
[1] 3
> set.seed(10)
> strn <- paste(sample(LETTERS, 10), collapse = "")
> strn
[1] "NHKPBEFTLY"
> nchar(strn)
[1] 10
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Scala list concatenation, ::: vs ++
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Legacy. List was originally defined to be functional-languages-looking:
1 :: 2 :: Nil // a li...
Python TypeError: not enough arguments for format string
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3 Answers
3
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Should I use a data.frame or a matrix?
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edited Aug 30 '17 at 0:12
answered Mar 1 '11 at 19:00
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Force point (“.”) as decimal separator in java
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answered Mar 8 '11 at 17:32
Jon SkeetJon Skeet
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How do you rename a table in SQLite 3.0?
How do you rename a table in SQLite 3.0?
2 Answers
2
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How does Django's Meta class work?
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Moon
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answered Apr 27 '12 at 3:04
TadeckTadeck
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Change a column type from Date to DateTime during ROR migration
...ge_date_format_in_my_table
Then in your migration file:
For Rails >= 3.2:
class ChangeDateFormatInMyTable < ActiveRecord::Migration
def up
change_column :my_table, :my_column, :datetime
end
def down
change_column :my_table, :my_column, :date
end
end
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How can I get nth element from a list?
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Look here, the operator used is !!.
I.e. [1,2,3]!!1 gives you 2, since lists are 0-indexed.
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