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Python extract pattern matches
...need to capture from regex. search for the pattern, if found, retrieve the string using group(index). Assuming valid checks are performed:
>>> p = re.compile("name (.*) is valid")
>>> result = p.search(s)
>>> result
<_sre.SRE_Match object at 0x10555e738>
>>>...
What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...y objects returned.
Consider:
class House
{
int Id { get; set; }
string Address { get; set; }
Person[] Inhabitants { get; set; }
}
class Person
{
string Name { get; set; }
int HouseId { get; set; }
}
and tables with a similar structure. A single query for the address "22 Va...
Search and replace a line in a file in Python
...
Note that files should be a string containing the file name, not a file object.
– atomh33ls
Aug 30 '13 at 10:00
...
Shorter syntax for casting from a List to a List?
...ist<object>();
o.Add("one");
o.Add("two");
o.Add(3);
IEnumerable<string> s1 = o.Cast<string>(); //fails on the 3rd item
List<string> s2 = o.ConvertAll(x => x.ToString()); //succeeds
share
...
E11000 duplicate key error index in mongodb mongoose
...
var userSchema = new mongoose.Schema({
local: {
name: { type: String },
email : { type: String, require: true, index:true, unique:true,sparse:true},
password: { type: String, require:true },
},
facebook: {
id : { type: String },
token : { type:...
How do I get the directory from a file's full path?
...are working with a FileInfo object, then there is an easy way to extract a string representation of the directory's full path via the DirectoryName property.
Description of the FileInfo.DirectoryName Property via MSDN:
Gets a string representing the directory's full path.
Sample usage:
stri...
machine learning libraries in C# [closed]
...2 helper classes:
public class TrainingSet
{
private readonly List<string> _attributes = new List<string>();
private readonly List<List<object>> _examples = new List<List<object>>();
public TrainingSet(params string[] attributes)
{
_attribu...
Google Maps API v2: How to make markers clickable?
...he original data model linked to the marker
private Map<Marker, Map<String, Object>> markers = new HashMap<>();
You will need a data model
private Map<String, Object> dataModel = new HashMap<>();
Put some data in the data model
dataModel.put("title", "My Spot");
...
Text Progress Bar in the Console [closed]
...equired : total iterations (Int)
prefix - Optional : prefix string (Str)
suffix - Optional : suffix string (Str)
decimals - Optional : positive number of decimals in percent complete (Int)
length - Optional : character length of bar (Int)
...
Set value to NULL in MySQL
...d'] == '')) {
$val = 'NULL';
} else {
$val = "'" . mysql_real_escape_string($_POST['nullfield']) . "'";
}
$sql = "INSERT INTO .... VALUES ($val)";
if you put 'NULL' into your query, then you're just inserting a 4-character string. Without the quotes, NULL is the actual null value.
...