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how to check the dtype of a column in python pandas
...know this is a bit of an old thread but with pandas 19.02, you can do:
df.select_dtypes(include=['float64']).apply(your_function)
df.select_dtypes(exclude=['string','object']).apply(your_other_function)
http://pandas.pydata.org/pandas-docs/version/0.19.2/generated/pandas.DataFrame.select_dtypes.h...
How to select only the records with the highest date in LINQ
...is:
var q = from n in table
group n by n.AccountId into g
select new {AccountId = g.Key, Date = g.Max(t=>t.Date)};
If you want the whole record:
var q = from n in table
group n by n.AccountId into g
select g.OrderByDescending(t=>t.Date).FirstOrDefault();
...
How to increase storage for Android Emulator? (INSTALL_FAILED_INSUFFICIENT_STORAGE)
...onfigurations". You can find that in the drop-down under the "debug" icon. Select "target", and select a preferred emulator target to launch. Then under "additional emulator command line options," add this:
-partition-size 1024
Then CLOSE the emulator (and remove any devices), and click the debug ...
How to add column if not exists on PostgreSQL?
...s, _col text, _type regtype)
RETURNS bool AS
$func$
BEGIN
IF EXISTS (SELECT 1 FROM pg_attribute
WHERE attrelid = _tbl
AND attname = _col
AND NOT attisdropped) THEN
RETURN FALSE;
ELSE
EXECUTE format('ALTER TABLE %s ADD COLUMN %I %s...
Truncating all tables in a Postgres database
...e IN VARCHAR) RETURNS void AS $$
DECLARE
statements CURSOR FOR
SELECT tablename FROM pg_tables
WHERE tableowner = username AND schemaname = 'public';
BEGIN
FOR stmt IN statements LOOP
EXECUTE 'TRUNCATE TABLE ' || quote_ident(stmt.tablename) || ' CASCADE;';
END LOO...
How can I select and upload multiple files with HTML and PHP, using HTTP POST?
... </body>
</html>
Here's what it looks like in Chrome after selecting 2 items in the file dialog:
And here's what it looks like after clicking the "Upload" button.
This is just a sketch of a fully working answer. See PHP Manual: Handling file uploads for more information on prop...
How do I obtain a Query Execution Plan in SQL Server?
...ution plan in SQL Server Management Studio, or right click on the plan and select "Save Execution Plan As ..." to save the plan to a file in XML format.
Method 2 - Using SHOWPLAN options
This method is very similar to method 1 (in fact this is what SQL Server Management Studio does internally), ho...
MySQL Error 1093 - Can't specify target table for update in FROM clause
...s question
In MySQL, you can't modify the same table which you use in the SELECT part.
This behaviour is documented at:
http://dev.mysql.com/doc/refman/5.6/en/update.html
Maybe you can just join the table to itself
If the logic is simple enough to re-shape the query, lose the subquery and join th...
How to create a GUID/UUID in Python
...UUID with the dashes included, while uuid4().hex returns "The UUID as a 32-character hexadecimal string"
– stuartd
Jan 30 '18 at 10:08
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What is this: [Ljava.lang.Object;?
... name consists of the name of the element type preceded by one or more '[' characters representing the depth of the array nesting.
The encoding of element type names is as follows:
Element Type Encoding
boolean Z
byte B
char C
double D...