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How to add /usr/local/bin in $PATH on Mac
...e OS X way. Paths on OS X are built using /usr/libexec/path_helper, called from the default /etc/profile. Start at man path_helper then add your paths in files in /etc/paths.d. You will find that pretty much every path setting example from other OSs includes $PATH because none of them seem to be abl...
Render a string in HTML and preserve spaces and linebreaks
...p that has a details page. As part of that I have a description (retrieved from a db) that has spaces and new lines. When it is rendered the new lines and spaces are ignored by the html. I would like to encode those spaces and new lines so that they aren't ignored.
...
IBOutlet and IBAction
...isible. This provides extra flexibility, al
All 3 of these are visible from Interface Builder:
-(void) someMethod1:(id) sender;
-(IBAction) someMethod2;
-(IBAction) someMethod3:(id) sender;
See Apple's Interface Builder User Guide for details, particularly the section entitled Xcode Integra...
What's the difference between belongs_to and has_one?
...
That is pretty much the same the accepted answer from two years ago already states.
– matthias krull
Oct 5 '12 at 18:26
11
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Enum String Name from Value
... member with a simple cast, and then call ToString():
int value = GetValueFromDb();
var enumDisplayStatus = (EnumDisplayStatus)value;
string stringValue = enumDisplayStatus.ToString();
share
|
imp...
Why are my basic Heroku apps taking two seconds to load?
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If your application is unused for a while it gets unloaded (from the server memory).
On the first hit it gets loaded and stays loaded until some time passes without anyone accessing it.
This is done to save server resources. If no one uses your app why keep resources busy and not...
Pandas percentage of total with groupby
... the sales column by its sum. Copying the beginning of Paul H's answer:
# From Paul H
import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
'office_id': list(range(1, 7)) * 2,
'sales': [np.random.rand...
In Objective-C, what is the equivalent of Java's “instanceof” keyword?
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From Wikipedia:
In Objective-C, for example, both the
generic Object and NSObject (in
Cocoa/OpenStep) provide the method
isMemberOfClass: which returns true if
the argument to the method is an
instance of the sp...
NSUserDefaults removeObjectForKey vs. setObject:nil
...l.
here is how to test if setting key value to nil removed the key entry from NSUserDefaults standardUserDefaults.
NSArray *keys = [[[NSUserDefaults standardUserDefaults] dictionaryRepresentation] allKeys] copy];
for(NSString *key in keys) {
NSLog(@"Key Name: %@", key);
}
[keys release]...
How to remove the first Item from a list?
..., if you are performing many pop(0), you should look at collections.deque
from collections import deque
>>> l = deque(['a', 'b', 'c', 'd'])
>>> l.popleft()
'a'
>>> l
deque(['b', 'c', 'd'])
Provides higher performance popping from left end of the list
...