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How to check for a valid URL in Java?
... it does not appear to work with newer domains such as .london etc
– V H
Jun 9 '15 at 14:36
how about intr...
List of tables, db schema, dump etc using the Python sqlite3 API
...
You can fetch the list of tables and schemata by querying the SQLITE_MASTER table:
sqlite> .tab
job snmptarget t1 t2 t3
sqlite> select name from sqlite_master where type = 'table';
job
t1
t2
s...
Current time formatting with Javascript
...ind. It sets it to the non-printable character, which it replaces later in order to avoid conflicts)
– Danegraphics
Apr 20 at 16:35
...
Sorting Python list based on the length of the string
...ey parameter:
xs.sort(key=lambda s: len(s))
This tells the sort method to order based on whatever the key function returns.
EDIT: Thanks to balpha and Ruslan below for pointing out that you can just pass len directly as the key parameter to the function, thus eliminating the need for a lambda:
xs.s...
Is Big O(logn) log base e?
... big-O notation is usually written showing only the asymptotically highest order of n, so constant coefficients will drop away. Since a different logarithm base is equivalent to a constant coefficient, it is superfluous.
That said, I would probably assume log base 2.
...
Selecting/excluding sets of columns in pandas [duplicate]
...-based method, so duplicate column names will cause issues, and the column order may be changed.
Advantage over drop: you don't create a copy of the entire dataframe when you only need the list of columns. For instance, in order to drop duplicates on a subset of columns:
# may create a copy of t...
What does it mean: The serializable class does not declare a static final serialVersionUID field? [d
... the serialization
(additional fields, removed fields,
change of field order, ...)
That's not correct, and you will be unable to cite an authoriitative source for that claim. It should be changed whenever you make a change that is incompatible under the rules given in the Versioning of Seriali...
How to find out if an item is present in a std::vector?
...
If your vector is not ordered, use the approach MSN suggested:
if(std::find(vector.begin(), vector.end(), item)!=vector.end()){
// Found the item
}
If your vector is ordered, use binary_search method Brian Neal suggested:
if(binary_searc...
Difference between solr and lucene
...work.
Examples are Solr, Elastic Search, LinkedIn (yes, under the hood), etc..
Check out this article: Lucene vs Solr
UPDATE (6/18/14)
When to use Lucene?
You are a search engineer AND
You are a programmer AND
You want full control over almost all the internals of Lucene AND
Your requirements...
Iterate over a Javascript associative array in sorted order
...nary-like object should I use if I want to iterate over the keys in sorted order?" then you might develop an object like this:
var a = {
keys : new Array(),
hash : new Object(),
set : function(key, value) {
if (typeof(this.hash[key]) == "undefined") { this.keys.push(key); }
this.hash[...