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How to iterate over values of an Enum having flags?
... .Split(new[] { ", " }, StringSplitOptions.None)
.Select(v => (Items)Enum.Parse(typeof(Items), v));
// This method will always end up with the most applicable values
value = Items.Bar | Items.Baz;
values = value.ToString()
.Split(new[] { ", " }, StringSplit...
CodeFile vs CodeBehind
...bute of the Page directive or is there a way to create a web project which selects codebehind or codefile, by default, each time a new web page is added?
– Matt W
Nov 5 '09 at 8:42
...
PSQLException: current transaction is aborted, commands ignored until end of transaction block
...t = connection.createStatement();
statement.executeQuery("select * from moobar");
//This SQL is correctly formed, yet it throws the
//'transaction is aborted' SQL Exception, why? Because:
//A. you were in a transaction.
//B. You ran a SQL stateme...
Convert pandas dataframe to NumPy array
...ution, in this case, to_numpy without explaining how to recover the column selecting functionality of as_matrix! I am sure there are other ways to select columns, but as_matrix was at least one of them!
– Jérémie
Jul 31 '19 at 23:50
...
How to join (merge) data frames (inner, outer, left, right)
...s these operations in SQL.
library(sqldf)
## inner join
df3 <- sqldf("SELECT CustomerId, Product, State
FROM df1
JOIN df2 USING(CustomerID)")
## left join (substitute 'right' for right join)
df4 <- sqldf("SELECT CustomerId, Product, State
FROM df1...
How can I use grep to show just filenames on Linux?
...andard:
-l
(The letter ell.) Write only the names of files containing selected
lines to standard output. Pathnames are written once per file searched.
If the standard input is searched, a pathname of (standard input) will
be written, in the POSIX locale. In other locales, standard i...
Weighted random numbers
...
if you have a bag of red and blue marbles and you select a red marble from it and don't replace it is the probability of selecting another red marble still the same? In the same way, your statement "Pick elements from the bag sequentially until it is empty" produces a totall...
Increment a database field by 1
...complex depending on your specific needs:
INSERT into mytable (logins)
SELECT max(logins) + 1
FROM mytable
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How do I create a simple 'Hello World' module in Magento?
...ck our work). In the admin application
Go to System->Cache Management
Select Refresh from the All Cache menu
Click Save Cache settings
Now, we make sure that Magento knows about the module
Go to System->Configuration
Click Advanced
In the "Disable modules output" setting box, look for yo...
Why should I avoid std::enable_if in function signatures
...{}
}
Tag dispatching does not manipulate the overload set, but helps you select exactly the function you want by providing the proper arguments through a compile-time expression (e.g. in a type trait). In my experience, this is much easier to debug and get right. If you are an aspiring library wri...