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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, ...
What is the benefit of zerofill in MySQL?
...
When you select a column with type ZEROFILL it pads the displayed value of the field with zeros up to the display width specified in the column definition. Values longer than the display width are not truncated. Note that usage of ZER...
Fragment onCreateView and onActivityCreated called twice
....getFragmentManager().findFragmentByTag(mTag);
}
public void onTabSelected(Tab tab, FragmentTransaction ft) {
if (mFragment == null) {
mFragment = Fragment.instantiate(mActivity, mClass.getName());
ft.replace(android.R.id.content, mFragment, mTag);
} ...
What is the point of the diamond operator () in Java 7?
...de by saving repeated type arguments. In practice, it's just two confusing chars more giving you nothing. Why?
No sane programmer uses raw types in new code. So the compiler could simply assume that by writing no type arguments you want it to infer them.
The diamond operator provides no type infor...
How to drop a table if it exists?
...
Is it correct to do the following?
IF EXISTS(SELECT *
FROM dbo.Scores)
DROP TABLE dbo.Scores
No. That will drop the table only if it contains any rows (and will raise an error if the table does not exist).
Instead, for a permanent table you can use
I...
Convert a string to int using sql query
...
You could use CAST or CONVERT:
SELECT CAST(MyVarcharCol AS INT) FROM Table
SELECT CONVERT(INT, MyVarcharCol) FROM Table
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How to remove a Gitlab project?
...
Go to the project page
Select "Settings"
Select the "General" section (you must be in the repository you want to delete to delete it)
If you have enough rights, then at the bottom of the page will be a button for "Advanced settings" (i.e. project s...
Proper way to rename solution (and directories) in Visual Studio
...story of the file. For example, with TortoiseSVN, right click on the file, select TortoiseSVN .. Rename.
In the .sln file, edit all instances of Project1 to be Project2, using a text editor like NotePad.
Restart Visual Studio, and everything will work as before, but with the project in a different ...
SQL Joins Vs SQL Subqueries (Performance)?
...e result i was looking for was 739 elements.
My query at first was this:
SELECT p.id,
p.fixedId,
p.azienda_id,
p.categoria_id,
p.linea,
p.tipo,
p.nome
FROM prodotto p
WHERE p.azienda_id = 2699 AND p.anno = (
SELECT MAX(p2.anno)
FROM prodotto p2
WHERE p2.fixed...
Add support library to Android Studio project
...oject Structure (Press F4 on PC and Command+; on MAC) on your project).
2.Select Modules on the left pane.
3.Choose your project and you will see Dependencies TAB above the third Column.
4.Click on the plus sign in the bottom. Then a tree-based directory chooser dialog will pop up, navigate to yo...