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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
...
What does the JSLint error 'body of a for in should be wrapped in an if statement' mean?
...type. Suppose you want all arrays to have a cool new function called filter_0 that will filter zeroes out.
Array.prototype.filter_0 = function() {
var res = [];
for (var i = 0; i < this.length; i++) {
if (this[i] != 0) {
res.push(this[i]);
}
}
return r...
Get generated id after insert
...LiteDatabase().insert("user", "", values) ;
If query exec use select last_insert_rowid()
String sql = "INSERT INTO [user](firstName,lastName) VALUES (\"Ahmad\",\"Aghazadeh\"); select last_insert_rowid()";
DBHelper itemType =new DBHelper();// your dbHelper
c = db.rawQuery(sql, null);
if (c.move...
Simple C example of doing an HTTP POST and consuming the response
...es have \r\n at the end.
A URL has the form of http://host:port/path?query_string
There are two main ways of submitting a request to a website:
GET: The query string is optional but, if specified, must be reasonably short. Because of this the header could just be the GET command and nothing else...
PHP_SELF vs PATH_INFO vs SCRIPT_NAME vs REQUEST_URI
... address is, so it will know what to do with the navigation. I've used mod_rewrite , as per CodeIgniter documentation.
9 A...
Best way to store date/time in mongodb
...ISODate()})
> db.test.insert({date: new Date()})
> db.test.find()
{ "_id" : ObjectId("..."), "date" : ISODate("2014-02-10T10:50:42.389Z") }
{ "_id" : ObjectId("..."), "date" : ISODate("2014-02-10T10:50:57.240Z") }
The native type supports a whole range of useful methods out of the box, which...
Run an OLS regression with Pandas Data Frame
... I accidentally typed formulas instead and got weird error: TypeError: from_formula() takes at least 3 arguments (2 given)
– denfromufa
Nov 14 '16 at 18:19
...
Why does IE9 switch to compatibility mode on my website?
...ility view’ button in that domain before;
perhaps also whether this has happened automatically due to some other content on the site causing IE8/9's renderer to crash and fall back to the old renderer;
whether the user has opted to put all sites in compatibility view by default;
whether IE thinks ...
Why does GCC generate such radically different assembly for nearly the same C code?
... why they are so different, first we must understand how GCC optimizes fast_trunc_one().
Believe it or not, fast_trunc_one() is being optimized to this:
int fast_trunc_one(int i) {
int mantissa, exponent;
mantissa = (i & 0x07fffff) | 0x800000;
exponent = 150 - ((i >> 23) &...
What are “Groovy” and “Grails” and what kinds of applications are built using them?
...lopment best practices, and is meant to be highly productive.
What kind of Applications are built using "Groovy on Grails"?
Grails is used to build web applications that run on the JVM.
What are the advantages of Groovy on Grails?
High productivity, focusing on business instead of plumbing. (Note ...