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How to remove last n characters from every element in the R vector
... an example of what I would do. I hope it's what you're looking for.
char_array = c("foo_bar","bar_foo","apple","beer")
a = data.frame("data"=char_array,"data2"=1:4)
a$data = substr(a$data,1,nchar(a$data)-3)
a should now contain:
data data2
1 foo_ 1
2 bar_ 2
3 ap 3
4 b 4
...
Append values to query string
...Fixture]
public class UriExtensionsTests {
[Test]
public void Add_to_query_string_dictionary_when_url_contains_no_query_string_and_values_is_empty_should_return_url_without_changing_it() {
Uri url = new Uri("http://www.domain.com/test");
var values = new Dictionary<string, s...
Is it possible to serialize and deserialize a class in C++?
...e it, here.
The only native way to do it is to use streams. That's essentially all the Boost::serialization library does, it extends the stream method by setting up a framework to write objects to a text-like format and read them from the same format.
For built-in types, or your own types with op...
What is the difference between Normalize.css and Reset CSS?
I know what CSS Reset is, but recently I heard about this new thing called Normalize.css
9 Answers
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How often does python flush to a file?
...t size.
A negative buffering means to use the system default, which is usually line buffered for tty devices and fully buffered for other files.
If omitted, the system default is used.
code:
bufsize = 0
f = open('file.txt', 'w', buffering=bufsize)
...
String formatting in Python 3
...format(goals=2, penalties=4)
"({goals} goals, ${penalties})".format(**self.__dict__)
"first goal: {0.goal_list[0]}".format(self)
"second goal: {.goal_list[1]}".format(self)
"conversion rate: {:.2f}".format(self.goals / self.shots) # '0.20'
"conversion rate: {:.2%}".format(self.goals / self.shots) ...
ssh: Could not resolve hostname [hostname]: nodename nor servname provided, or not known
...rite out my router's port forwarding settings.
(ApplicationTextField)_ssh (external port)_22 (Internal Port)_22 (Protocal)_Both (To IP Address)_192.168.1.### (Enabled)_checkBox
Port forwarding settings can be different for different routers though, so look ...
How do I execute any command editing its file (argument) “in place” using bash?
...
This is an answer. I was actually wondering if there is a generic solution to this problem. For example if I want to find all UNIQ lines in a file "in place", I can't do -o
– jm.
Sep 28 '08 at 21:45
...
What do ellipsis […] mean in a list?
... an infinite loop of references, so it decided to cut it short, it's not really infinite. And no, it's not really useful besides a thought experiment :)
– Óscar López
Jun 18 '13 at 3:44
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Is it possible to write to the console in colour in .NET?
Writing a small command line tool, it would be nice to output in different colours. Is this possible?
8 Answers
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