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Replacing column values in a pandas DataFrame
...a column (the second 'female' in your w['female']['female']) doesn't mean "select rows where the value is 'female'". It means to select rows where the index is 'female', of which there may not be any in your DataFrame.
shar...
Modifying a subset of rows in a pandas dataframe
...The df.A==0 expression creates a boolean series that indexes the rows, 'B' selects the column. You can also use this to transform a subset of a column, e.g.:
df.loc[df.A==0, 'B'] = df.loc[df.A==0, 'B'] / 2
I don't know enough about pandas internals to know exactly why that works, but the basic is...
How do I find out my MySQL URL, host, port and username?
...If you're already logged into the command line client try this:
mysql> select user();
It will output something similar to this:
+----------------+
| user() |
+----------------+
| root@localhost |
+----------------+
1 row in set (0.41 sec)
In my example above, I was logged in as root...
How to change package name of an Android Application
...
Right-click on the package name (src/com.android.gesture.builder).
Select Refactor > Rename and change the name, for example to
com.android.gestureNEW.builder.
Open the manifest file. Inside the
<manifest> tag, change the package name to
com.android.gestureNEW.builder.
...
What is Func, how and when is it used
...ied to any particular functionality.
For example, consider the Enumerable.Select extension method.
The pattern is: for every item in a sequence, select some value from that item (e.g., a property) and create a new sequence consisting of these values.
The placeholder is: some selector function tha...
How to update column with null value
...Hello');
UPDATE your_table
SET your_column = NULL
WHERE some_id = 1;
SELECT * FROM your_table WHERE your_column IS NULL;
+---------+-------------+
| some_id | your_column |
+---------+-------------+
| 1 | NULL |
+---------+-------------+
1 row in set (0.00 sec)
...
JPA : How to convert a native query result set to POJO class collection
...e done with an entity.
For instance:
Query query = em.createNativeQuery("SELECT name,age FROM jedi_table", Jedi.class);
@SuppressWarnings("unchecked")
List<Jedi> items = (List<Jedi>) query.getResultList();
But in this case, Jedi, must be a mapped entity class.
An alternative to avoi...
SQL JOIN - WHERE clause vs. ON clause
...
They are not the same thing.
Consider these queries:
SELECT *
FROM Orders
LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID
WHERE Orders.ID = 12345
and
SELECT *
FROM Orders
LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID
AND Orders.ID = 12345
The first will re...
Android Studio - How to Change Android SDK Path
...ject Structure into Project Structure
Left -> SDK Location
SDK location select Android SDK location (old version use Press +, add another sdk)
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How to style the with only CSS?
How can I style <option> s of a <select> element with cross-browser compatibility? I know many JavaScript ways which customize the dropdown to convert into <li> , which I'm not asking about.
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