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Compare two DataFrames and output their differences side-by-side
...original question
The first step is to concatenate the DataFrames horizontally with the concat function and distinguish each frame with the keys parameter:
df_all = pd.concat([df.set_index('id'), df2.set_index('id')],
axis='columns', keys=['First', 'Second'])
df_all
It's pr...
What do I have to do to get Core Data to automatically migrate models?
...AndKeys:
[NSNumber numberWithBool:YES], NSMigratePersistentStoresAutomaticallyOption,
[NSNumber numberWithBool:YES], NSInferMappingModelAutomaticallyOption, nil];
NSError *error;
_persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel: [self managedObjectMod...
Rails 3: Get Random Record
...; rand(Thing.count))
# Rails 3
Thing.offset(rand(Thing.count)).first
Actually, in Rails 3 all examples will work. But using order RANDOM is quite slow for big tables but more sql-style
UPD. You can use the following trick on an indexed column (PostgreSQL syntax):
select *
from my_table
where i...
SLF4J: Class path contains multiple SLF4J bindings
...
is the version (slf4j-log4j12) applicable for all? or should we find out the version from mvn dependency:tree?
– Lei Yang
Nov 11 '19 at 7:07
add a...
How to remove an HTML element using Javascript?
...em);
return false;
}
But you don't need (or want) a form for that at all, not if its sole purpose is to remove the dummy div. Instead:
HTML:
<input type="button" value="Remove DUMMY" onclick="removeDummy()" />
JavaScript:
function removeDummy() {
var elem = document.getElementBy...
Does Python optimize tail recursion?
...tracebacks:
Tail Recursion Elimination (2009-04-22)
Final Words on Tail Calls (2009-04-27)
You can manually eliminate the recursion with a transformation like this:
>>> def trisum(n, csum):
... while True: # Change recursion to a while loop
... if n == 0:...
Convert a Unicode string to a string in Python (containing extra symbols)
...
This breaks if the content of the string is actually unicode, not just ascii characters in a unicode string. Don't do this, you'll get random UnicodeEncodeError exceptions all over the place.
– Doug
Oct 9 '13 at 7:31
...
How can I check if a string represents an int, without using try/except?
...
If you're really just annoyed at using try/excepts all over the place, please just write a helper function:
def RepresentsInt(s):
try:
int(s)
return True
except ValueError:
return False
>>> pri...
Do we need semicolon at the end? [duplicate]
...andable manner using examples under the headings:
Where Semicolons are Allowed
Where Semicolons May be Omitted
The rules
It even digs into the official ECMAScript specification about the topic.
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How to get the ActionBar height?
...f the ActionBar (using Sherlock) every time an activity is created (specially to handle configuration changes on rotation where the ActionBar height might change).
...