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“Large data” work flows using pandas
... one contains different fields, or do they have some records per file with all of the fields in each file?
Do you ever select subsets of rows (records) based on criteria (e.g. select the rows with field A > 5)? and then do something, or do you just select fields A, B, C with all of the records (a...
How to split a string literal across multiple lines in C / Objective-C?
...
There are two ways to split strings over multiple lines:
Using \
All lines in C can be split into multiple lines using \.
Plain C:
char *my_string = "Line 1 \
Line 2";
Objective-C:
NSString *my_string = @"Line1 \
Line2";
Better approach
Th...
Slow Requests on Local Flask Server
... localhost
Once I do this the latency problems go away.
I'm really digging Flask and I'm glad that it's not a problem with the framework. I knew it couldn't be.
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ObservableCollection not noticing when Item in it changes (even with INotifyPropertyChanged)
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The ContentList's Set method will not get called when you change a value inside the collection, instead you should be looking out for the CollectionChanged event firing.
public class CollectionViewModel : ViewModelBase
{
public ObservableCollection<E...
Downloading Java JDK on Linux via wget is shown license page instead
...2b6607d096fa80163/jdk-8u131-linux-x64.rpm > jdk-8u112-linux-x64.rpm
In all cases above, subst 'i586' for 'x64' to download the 32-bit build.
-j -> junk cookies
-k -> ignore certificates
-L -> follow redirects
-H [arg] -> headers
curl can be used in place of wget.
UPDATE FOR JDK 7u7...
Representing graphs (data structure) in Python
...f._graph[node2].add(node1)
def remove(self, node):
""" Remove all references to node """
for n, cxns in self._graph.items(): # python3: items(); python2: iteritems()
try:
cxns.remove(node)
except KeyError:
pass
tr...
What does $_ mean in PowerShell?
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This is the variable for the current value in the pipe line, which is called $PSItem in Powershell 3 and newer.
1,2,3 | %{ write-host $_ }
or
1,2,3 | %{ write-host $PSItem }
For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable ...
How do I use prepared statements in SQlite in Android?
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I use prepared statements in Android all the time, it's quite simple :
SQLiteDatabase db = dbHelper.getWritableDatabase();
SQLiteStatement stmt = db.compileStatement("INSERT INTO Country (code) VALUES (?)");
stmt.bindString(1, "US");
stmt.executeInsert();
...
Define css class in django Forms
... The only sane solution, I must say. Thank you!. Python code, and especially in form's definition, is the last place to put stuff for styling - these definitely belong to the templates.
– Boris Chervenkov
Nov 12 '11 at 23:09
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Determining Referer in PHP
...s the most reliable and secure way to determine what page either sent, or called (via AJAX), the current page. I don't want to use the $_SERVER['HTTP_REFERER'] , because of the (lack of) reliability, and I need the page being called to only come from requests originating on my site.
Edit: I am...