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Change column type from string to float in Pandas
...options for converting types in pandas:
to_numeric() - provides functionality to safely convert non-numeric types (e.g. strings) to a suitable numeric type. (See also to_datetime() and to_timedelta().)
astype() - convert (almost) any type to (almost) any other type (even if it's not necessarily se...
Are Stored Procedures more efficient, in general, than inline statements on modern RDBMS's? [duplica
...e DBMS!) may operate
contrary to this, so you'll want to
double-check with your target DBMS
before assuming all of this still holds.
I've been a Sybase ASE, MySQL, and SQL Server DBA on-and off since for almost a decade (along with application development in C, PHP, PL/SQL, C#.NET, and Ru...
Test if number is odd or even
... most basic way to find out if a number/variable is odd or even in PHP?
Is it something to do with mod?
17 Answers
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How to check whether a given string is valid JSON in Java
How do I validate a JSON string in Java? Or could I parse it using regular expressions?
19 Answers
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PHP validation/regex for URL
...for URLs, does anybody have one handy that works well? I didn't find one with the zend framework validation classes and have seen several implementations.
...
What's the best practice for putting multiple projects in a git repository? [closed]
As some reason, I only have one repository to use.
But I have multiple projects including java projects, php scripts and Android apps projects.
...
How to convert date to timestamp?
...
Split the string into its parts and provide them directly to the Date constructor:
Update:
var myDate = "26-02-2012";
myDate = myDate.split("-");
var newDate = new Date( myDate[2], myDate[1] - 1, myDate[0]);
console.log(newD...
Find when a file was deleted in Git
I have a Git repository with n commits.
6 Answers
6
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Reason for Column is invalid in the select list because it is not contained in either an aggregate f
...uld the value of b show on each of these two rows? There are three possibilities in each case, and nothing in the query makes it clear which value to choose for b in each group. It's ambiguous.
This demonstrates the single-value rule, which prohibits the undefined results you get when you run a GRO...
Differences between Exception and Error
...ions are the bread and butter of exception handling. The Javadoc explains it well:
An Error is a subclass of Throwable that indicates serious problems that a
reasonable application should not try to catch. Most such errors are abnormal
conditions.
Look at a few of the subclasses of Error,...