apply, the Convenience Function you Never Needed We start by addressing the questions in the OP, one by one. “If apply is so bad, then why is it in the API?” DataFrame.apply and Series.apply are convenience functions defined on DataFrame and Series object respectively. apply accepts any user defined function that applies a transformation/aggregation on … Read more
Why is Ruby considered slow? Because if you run typical benchmarks between Ruby and other languages, Ruby loses. I do not find Ruby to be slow but then again, I’m just using it to make simple CRUD apps and company blogs. What sort of projects would I need to be doing before I find Ruby … Read more
I don’t want to return a copied value because it’s inefficient Prove it. Look up RVO and NRVO, and in C++0x move-semantics. In most cases in C++03, an out parameter is just a good way to make your code ugly, and in C++0x you’d actually be hurting yourself by using an out parameter. Just write … Read more
Patience, technical skill and endurance. First point is that a DX Demo is primarily a teaching aid so it’s done for clarity not speed of execution. It’s a pretty big subject to condense but games development is primarily about understanding your data and your execution paths to an almost pathological degree. Your code is designed … Read more
Depends on what you need, in general I think that: You should not care too much about performances. Redis is faster per core with small values, but memcached is able to use multiple cores with a single executable and TCP port without help from the client. Also memcached is faster with big values in the … Read more
A Pipe() can only have two endpoints. A Queue() can have multiple producers and consumers. When to use them If you need more than two points to communicate, use a Queue(). If you need absolute performance, a Pipe() is much faster because Queue() is built on top of Pipe(). Performance Benchmarking Let’s assume you want … Read more
If you want a more accurate measurement than the answer above: set statistics time on — Query 1 goes here — Query 2 goes here set statistics time off The results will be in the Messages window. Update (2015-07-29): By popular request, I have written a code snippet that you can use to time an … Read more
Doing the following: data.substring(x, y) + “” creates a new (smaller) String object, and throws away the reference to the String created by substring(), thus enabling garbage collection of this. The important thing to realise is that substring() gives a window onto an existing String – or rather, the character array underlying the original String. … Read more
Yes – absolutely. Looking up a class via reflection is, by magnitude, more expensive. Quoting Java’s documentation on reflection: Because reflection involves types that are dynamically resolved, certain Java virtual machine optimizations can not be performed. Consequently, reflective operations have slower performance than their non-reflective counterparts, and should be avoided in sections of code which … Read more
How to throttle requestAnimationFrame to a specific frame rate Demo throttling at 5 FPS: http://jsfiddle.net/m1erickson/CtsY3/ This method works by testing the elapsed time since executing the last frame loop. Your drawing code executes only when your specified FPS interval has elapsed. The first part of the code sets some variables used to calculate elapsed time. … Read more