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Adding a Method to an Existing Object Instance
...ion foo at 0x00A98D70>
>>> a.bar
<bound method A.bar of <__main__.A instance at 0x00A9BC88>>
>>>
Bound methods have been "bound" (how descriptive) to an instance, and that instance will be passed as the first argument whenever the method is called.
Callables that ar...
The object 'DF__*' is dependent on column '*' - Changing int to double
...
Try this:
Remove the constraint DF_Movies_Rating__48CFD27E before changing your field type.
The constraint is typically created automatically by the DBMS (SQL Server).
To see the constraint associated with the table, expand the table attributes in Object ex...
Python dictionary: Get list of values for list of keys
...n list-comp:
Build list and throw exception if key not found: map(mydict.__getitem__, mykeys)
Build list with None if key not found: map(mydict.get, mykeys)
Alternatively, using operator.itemgetter can return a tuple:
from operator import itemgetter
myvalues = itemgetter(*mykeys)(mydict)
# use ...
Using variables inside a bash heredoc
...text in a variable.
Name='Rich Ba$tard'
dough='$$$dollars$$$'
cat <<____HERE
$Name, you can win a lot of $dough this week!
Notice that \`backticks' need escaping if you want
literal text, not `pwd`, just like in variables like
\$HOME (current value: $HOME)
____HERE
Demo: https://ideone.com/...
How to assign colors to categorical variables in ggplot2 that have stable mapping?
...er.pal(5,"Set1")
names(myColors) <- levels(dat$grp)
colScale <- scale_colour_manual(name = "grp",values = myColors)
and then add the color scale onto the plot as needed:
#One plot with all the data
p <- ggplot(dat,aes(x,y,colour = grp)) + geom_point()
p1 <- p + colScale
#A second plo...
Enable access control on simple HTTP server
...mport sys
class CORSRequestHandler (SimpleHTTPRequestHandler):
def end_headers (self):
self.send_header('Access-Control-Allow-Origin', '*')
SimpleHTTPRequestHandler.end_headers(self)
if __name__ == '__main__':
test(CORSRequestHandler, HTTPServer, port=int(sys.argv[1]) if le...
How to remove illegal characters from path and filenames?
...blic string ReplaceInvalidChars(string filename)
{
return string.Join("_", filename.Split(Path.GetInvalidFileNameChars()));
}
This answer was on another thread by Ceres, I really like it neat and simple.
share
...
Is there a performance difference between a for loop and a for-each loop?
...g4j.Marker, org.apache.logging.log4j.Marker...);
Code:
0: iconst_0
1: istore_2
2: aload_1
3: arraylength
4: istore_3
5: iload_2
6: iload_3
7: if_icmpge 29
10: aload_1
11: iload_2
12: aaload
13: astore 4
...
Extract substring in Bash
Given a filename in the form someletters_12345_moreleters.ext , I want to extract the 5 digits and put them into a variable.
...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...(think US States, Country Codes) and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
14 ...