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How to call a parent class function from derived class function?
...disambiguate it by adding the base class's name followed by two colons base_class::foo(...). You should note that unlike Java and C#, C++ does not have a keyword for "the base class" (super or base) since C++ supports multiple inheritance which may lead to ambiguity.
class left {
public:
void f...
Convert Dictionary to semicolon separated string in c#
...
Edited according to comments.
– the_drow
Oct 6 '10 at 11:18
7
@Amittai, @the_dr...
MySQL: determine which database is selected?
After calling mysql_select_db to grab a database, is there any way to later output the name of the database that is currently selected? This seems very basic but I couldn't find anything on php.net or stackoverflow (all results are for "no database selected").
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In Perl, how can I read an entire file into a string?
...
before reading from the file handle. See How can I read in an entire file all at once?, or
$ perldoc -q "entire file"
See Variables related to filehandles in perldoc perlvar and perldoc -f local.
Incidentally, if you can put your script on the server, you can have all the modules you want. See ...
MongoDB atomic “findOrCreate”: findOne, insert if nonexistent, but do not update
as the title says, I want to perform a find (one) for a document, by _id, and if doesn't exist, have it created, then whether it was found or was created, have it returned in the callback.
...
How to parse JSON in Scala using standard Scala classes?
... {
"languages": [{
"name": "English",
"is_active": true,
"completeness": 2.5
}, {
"name": "Latin",
"is_active": false,
"completeness": 0.9
}]
}
""".stripMargin
val result = for {
Some(M(m...
How can the Euclidean distance be calculated with NumPy?
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There's a function for that in SciPy. It's called Euclidean.
Example:
from scipy.spatial import distance
a = (1, 2, 3)
b = (4, 5, 6)
dst = distance.euclidean(a, b)
share
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Convert unix time to readable date in pandas dataframe
...12.15
3 1349979305 12.19
4 1350065705 12.15
In [25]: df['date'] = pd.to_datetime(df['date'],unit='s')
In [26]: df.head()
Out[26]:
date price
0 2012-10-08 18:15:05 12.08
1 2012-10-09 18:15:05 12.35
2 2012-10-10 18:15:05 12.15
3 2012-10-11 18:15:05 12.19
4 2012-10-12 18:15:...
design a stack such that getMinimum( ) should be O(1)
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EDIT: This fails the "constant space" constraint - it basically doubles the space required. I very much doubt that there's a solution which doesn't do that though, without wrecking the runtime complexity somewhere (e.g. making push/pop O(n)). Note that this doesn't change the complex...
Are PHP functions case sensitive?
I was digging through some code, and I found some calls to mySQL_fetch_array . Is PHP case sensitive about function names? I recall reading this somewhere but can't seem to find any reference to it.
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