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Normalize data in pandas
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Select the subset and compute as before. See pandas.pydata.org/pandas-docs/stable/indexing.html on how to index and select data
– Wouter Overmeire
Oct 19 '15 at 6:43
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MySQL: Invalid use of group function
..., not WHERE.
The difference is: the WHERE clause filters which rows MySQL selects. Then MySQL groups the rows together and aggregates the numbers for your COUNT function.
HAVING is like WHERE, only it happens after the COUNT value has been computed, so it'll work as you expect. Rewrite your subque...
Using 'starts with' selector on individual class names
...thought of using space in there. Can one use boolean operators in a jquery selector? Ideally, the above would be 'OR' to avoid the (rare and likely avoidable) case where there are more than one class staring with 'apple-'
– DA.
Feb 1 '10 at 17:12
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How can I calculate the number of lines changed between two commits in git?
...2>
but you can use --numstat or --shortstat as well. git log can also select commits in a variety other ways - have a look at the documentation. You might be interested in things like --since (rather than specifying commit ranges, just select commits since last week) and --no-merges (merge comm...
How to set a default value for an existing column
...able and found this way to check if it had been done already... IF EXISTS(SELECT * FROM information_schema.columns WHERE table_name='myTable' AND column_name='myColumn' AND Table_schema = 'myDBO' AND column_default IS NULL) BEGIN ALTER TABLE [myDBO].[myTable] ADD DEFAULT 0 FOR [myColumn] END
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How to log PostgreSQL queries?
...ement = 'all'
#logging_collector = off to logging_collector = on
Optional: SELECT set_config('log_statement', 'all', true);
sudo /etc/init.d/postgresql restart or sudo service postgresql restart
Fire query in postgresql select 2+2
Find current log in /var/lib/pgsql/9.2/data/pg_log/
The log files t...
Static hosting on Amazon S3 - DNS Configuration
...site. With the AWS console ( https://console.aws.amazon.com/s3/ ) you can select your bucket, click properties, then select the "Website" tab. Click enabled and set your index document to "index.html" and your error document to "404.html". You will also need to set your bucket with access permissi...
When to use UICollectionView instead of UITableView?
...onview, you don't need to set buttons with tags or other things by getting selected items values. You can simply get -(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath and in UITableViewDelegate:
`-(void)tableView:(UITableView *)tableView didS...
Resolving LNK4098: defaultlib 'MSVCRT' conflicts with
...ry time I want to create an application in VC++.
Right-click the project, select Properties then under 'Configuration properties | C/C++ | Code Generation', select "Multi-threaded Debug (/MTd)" for Debug configuration.
Note that this does not change the setting for your Release configuration - you...
How do I clone a range of array elements to a new array?
...want to do Cloning, not just copying references.
In this case you can use .Select to project array members to their clones.
For example, if your elements implemented IClonable you could do something like this:
var newArray = array.Skip(3).Take(5).Select(eachElement => eachElement.Clone()).ToArra...