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What do the terms “CPU bound” and “I/O bound” mean?
...U (doing calculations). A program that computes new digits of π will typically be CPU-bound, it's just crunching numbers.
A program is I/O bound if it would go faster if the I/O subsystem was faster. Which exact I/O system is meant can vary; I typically associate it with disk, but of course networ...
find vs find_by vs where
...
Use whichever one you feel suits your needs best.
The find method is usually used to retrieve a row by ID:
Model.find(1)
It's worth noting that find will throw an exception if the item is not found by the attribute that you supply. Use where (as described below, which will return an empty arr...
Objective-C and Swift URL encoding
...ww";
NSString *escapedString = [unescaped stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLHostAllowedCharacterSet]];
NSLog(@"escapedString: %@", escapedString);
NSLog output:
escapedString: http%3A%2F%2Fwww
The following are useful URL encoding character sets:
URLFragm...
How does JavaScript .prototype work?
...ing languages but I've written my fair share of JavaScript code. I never really got my head around this prototype-based programming, does any one know how this works?
...
Google Maps API 3 - Custom marker color for default (dot) marker
...s of other questions similar to this ( here , here and here ), but they all have accepted answers that don't solve my problem. The best solution I have found to the problem is the StyledMarker library, which does let you define custom colours for markers, but I can't get it to use the default m...
Mercurial .hgignore for Visual Studio 2008 projects
...
Here's my standard .hgignore file for use with VS2008 that was originally modified from a Git ignore file:
# Ignore file for Visual Studio 2008
# use glob syntax
syntax: glob
# Ignore Visual Studio 2008 files
*.obj
*.exe
*.pdb
*.user
*.aps
*.pch
*.vspscc
*_i.c
*_p.c
*.ncb
*.suo
*.tlb
*.tlh
...
Is there a setting on Google Analytics to suppress use of cookies for users who have not yet given c
... implement a mechanism where, on first visit, Google Analytics is automatically disabled in the absence of an opt-in cookie (cookies that determine cookie preferences are explicitly allowed), and then, if an opt-in happens, re-runs Google Analytics. On subsequent pageviews, all would run smoothly.
...
How to use single storyboard uiviewcontroller for multiple subclass
...do what you propose because there are no initializers in UIStoryboard that allow overriding the view controller associated with the storyboard as defined in the object details in the storyboard on initialization. It's at initialization that all the UI elements in the stoaryboard are linked up to th...
Why does += behave unexpectedly on lists?
...
The general answer is that += tries to call the __iadd__ special method, and if that isn't available it tries to use __add__ instead. So the issue is with the difference between these special methods.
The __iadd__ special method is for an in-place addition, that i...
Finding a branch point with Git?
... B. Here are three ways that I found, after a bit of tinkering:
1. visually, with gitk:
You should visually see a tree like this (as viewed from master):
or here (as viewed from topic):
in both cases, I've selected the commit that is B in my graph. Once you click on it, its full SHA is p...