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Warning message: In `…` : invalid factor level, NA generated
... "Type" to be a character.
> fixed <- data.frame("Type" = character(3), "Amount" = numeric(3))
> str(fixed)
'data.frame': 3 obs. of 2 variables:
$ Type : Factor w/ 1 level "": NA 1 1
$ Amount: chr "100" "0" "0"
>
> fixed <- data.frame("Type" = character(3), "Amount" = nume...
Fastest way to determine if an integer is between two integers (inclusive) with known sets of values
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535
There's an old trick to do this with only one comparison/branch. Whether it'll really improve s...
What are the differences between segment trees, interval trees, binary indexed trees and range trees
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327
+25
All the...
TypeError: got multiple values for argument
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232
This happens when a keyword argument is specified that overwrites a positional argument. For ex...
How to display an unordered list in two columns?
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384
Modern Browsers
leverage the css3 columns module to support what you are looking for.
http:/...
Python Empty Generator Function
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135
You can use return once in a generator; it stops iteration without yielding anything, and thus ...
Overwrite single file in my current branch with the same file in the master branch?
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edited Jun 28 '14 at 16:53
prayagupd
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answ...
Best way to reverse a string
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edited Nov 4 '17 at 19:32
Ofer Zelig
15.4k77 gold badges5151 silver badges8787 bronze badges
answered...
How do I replace the *first instance* of a string in .NET?
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135
string ReplaceFirst(string text, string search, string replace)
{
int pos = text.IndexOf(sear...