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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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Export a graph to .eps file with R
...alues. Read ?postscript for the details.
Here is an example:
postscript("foo.eps", horizontal = FALSE, onefile = FALSE, paper = "special")
plot(1:10)
dev.off()
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improve this answer
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How can I determine the type of an HTML element in JavaScript?
...bute you are looking for. For example:
var elt = document.getElementById('foo');
console.log(elt.nodeName);
Note that nodeName returns the element name capitalized and without the angle brackets, which means that if you want to check if an element is an <div> element you could do it as foll...
Rails: How to list database tables/objects using the Rails console?
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ActiveRecord::Base.connection.columns("foos") should also work, but it returns column objects, .map{|c| [c.name, c.type] } on the end fixes that.
– cwninja
Jan 20 '10 at 10:15
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What's the safest way to iterate through the keys of a Perl hash?
...iece of
code), it will continue at this position.
Example:
my %hash = ( foo => 1, bar => 2, baz => 3, quux => 4 );
# find key 'baz'
while ( my ($k, $v) = each %hash ) {
print "found key $k\n";
last if $k eq 'baz'; # found it!
}
# later ...
print "the hash contains:\n";
# i...
How to change color in markdown cells ipython/jupyter notebook?
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You can simply use raw html tags like
foo <font color='red'>bar</font> foo
Be aware that this will not survive a conversion of the notebook to latex.
As there are some complaints about the deprecation of the proposed solution. They are totally vali...
Difference between ref and out parameters in .NET [duplicate]
...d but passing it as a ref parameter it has to be set to something.
int x;
Foo(out x); // OK
int y;
Foo(ref y); // Error: y should be initialized before calling the method
Ref parameters are for data that might be modified, out parameters are for data that's an additional output for the function ...
What is the difference between call and apply?
...s Refers to When a Function is Called
When calling a function of the form foo.bar.baz(), the object foo.bar is referred to as the receiver. When the function is called, it is the receiver that is used as the value for this:
var obj = {};
obj.value = 10;
/** @param {...number} additionalValues */
o...
jQuery form serialize - empty string
...iv id="div2">
<input id="input1" type="text" value="2" name="foo"/>
</div>
</form>
will give you in the alert box foo=2.
.serialize() takes the name and the value of the form fields and creates a string like name1=value1&name2=value2. Without a name it can...
How to make connection to Postgres via Node.js
... the following:
const { Pool } = require('pg');
var config = {
user: 'foo',
database: 'my_db',
password: 'secret',
host: 'localhost',
port: 5432,
max: 10, // max number of clients in the pool
idleTimeoutMillis: 30000
};
const pool = new Pool(config);
pool.on('error'...