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How to take column-slices of dataframe in pandas
...e .loc
See the deprecation in the docs
.loc uses label based indexing to select both rows and columns. The labels being the values of the index or the columns. Slicing with .loc includes the last element.
Let's assume we have a DataFrame with the following columns:
foo, bar, quz, ant, cat, ...
How to configure Visual Studio to use Beyond Compare
...
In Visual Studio, go to the Tools menu, select Options, expand Source Control, (In a TFS environment, click Visual Studio Team Foundation Server), and click on the Configure User Tools button.
Click the Add button.
Enter/select the following options for Compar...
ruby on rails f.select options with custom attributes
I have a form select statement, like this:
5 Answers
5
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Add primary key to existing table
...PMID)
edit:
you can find the constraint name by using the query below:
select OBJECT_NAME(OBJECT_ID) AS NameofConstraint
FROM sys.objects
where OBJECT_NAME(parent_object_id)='Persion'
and type_desc LIKE '%CONSTRAINT'
sh...
iOS app with framework crashed on device, dyld: Library not loaded, Xcode 6 Beta
...r Products folder in your project.
Right click on your .framework and select "Show in Finder".
3) Place framework in your project
Drag and drop the .framework from your Finder window to your app project's "Framework" folder.
4) Configure app project for framework
Select the top leve...
What is the best collation to use for MySQL with PHP? [closed]
...ng utf8_general_ci.
MySQL will not distinguish between some characters in select statements, if the utf8_general_ci collation is used. This can lead to very nasty bugs - especially for example, where usernames are involved. Depending on the implementation that uses the database tables, this problem...
MySQL and GROUP_CONCAT() maximum length
...You should use it like this.
SET SESSION group_concat_max_len = 1000000;
select group_concat(column) from table group by column
You can do this even in sharing hosting, but when you use an other session, you need to repeat the SET SESSION command.
...
Return number of rows affected by UPDATE statements
...NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
DECLARE @RowCount1 INTEGER
DECLARE @RowCount2 INTEGER
DECLARE @RowCount3 INTEGER
DECLARE @RowCount4 INTEGER
UPDATE Table1 Set Column = 0 WHERE Column IS NULL
SEL...
PostgreSQL: Difference between text and varchar (character varying)
... article does detailed testing to show that the performance of inserts and selects for all 4 data types are similar. It also takes a detailed look at alternate ways on constraining the length when needed. Function based constraints or domains provide the advantage of instant increase of the length c...
How do you configure an OpenFileDialog to select folders?
In VS .NET, when you are selecting a folder for a project, a dialog that looks like an OpenFileDialog or SaveFileDialog is displayed, but is set up to accept only folders. Ever since I've seen this I've wanted to know how it's done. I am aware of the FolderBrowserDialog, but I've never really like...