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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...
Find the host name and port using PSQL commands
...
SELECT *
FROM pg_settings
WHERE name = 'port';
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How to parse JSON in Java
... JSON Generation through object serialisation
Support for collection type selection during parsing process
It can be used like this:
JsonParserFactory factory=JsonParserFactory.getInstance();
JSONParser parser=factory.newJsonParser();
Map jsonMap=parser.parseJson(jsonString);
...
Is a LINQ statement faster than a 'foreach' loop?
...ter than a flat foreach, but most likely you wouldn't have done a blanket "select * from foo" anyway, so that isn't necessarily a fair comparison.
Re PLINQ; parallelism may reduce the elapsed time, but the total CPU time will usually increase a little due to the overheads of thread management etc.
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Python loop counter in a for loop [duplicate]
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Use enumerate() like so:
def draw_menu(options, selected_index):
for counter, option in enumerate(options):
if counter == selected_index:
print " [*] %s" % option
else:
print " [ ] %s" % option
options = ['Option 0', 'Option...
Reading Excel files from C#
...ed Properties=Excel 8.0;", fileName);
var adapter = new OleDbDataAdapter("SELECT * FROM [workSheetNameHere$]", connectionString);
var ds = new DataSet();
adapter.Fill(ds, "anyNameHere");
DataTable data = ds.Tables["anyNameHere"];
This is what I usually use. It is a little different because I u...
Spring CrudRepository findByInventoryIds(List inventoryIdList) - equivalent to IN clause
... specify the @Query yourself. Something like this should work:
@Query( "select o from MyObject o where inventoryId in :ids" )
List<MyObject> findByInventoryIds(@Param("ids") List<Long> inventoryIdList);
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foreach with index [duplicate]
...
You can do the following
foreach (var it in someCollection.Select((x, i) => new { Value = x, Index = i }) )
{
if (it.Index > SomeNumber) //
}
This will create an anonymous type value for every entry in the collection. It will have two properties
Value: with the ori...
Moving Files into a Real Folder in Xcode
... Xcode should now be red (that's OK!).
From the Identity and Type manager, select the Group in Xcode that you want to relocate, then click the folder icon from the info pane:
In the Finder selection dialog, locate the equivalent new folder you created for this group in step 2. All the files insid...
How to elegantly deal with timezones
... }
...
}
4 - Here we can get the list of timezone to show to user to select from a dropdownbox:
public class ListHelper
{
public IEnumerable<SelectListItem> GetTimeZoneList()
{
var list = from tz in TimeZoneInfo.GetSystemTimeZones()
select new SelectLi...