Errata for Core Animation for Mac OS X and the iPhone

#41134: (Duplicate of #35393, reported on PDF page 26 seven months prior to the latest printing.)

The book indicates that x needs to be interpolated for 13 points between 0 and 0.25 (exclusive), giving 15 points (or 14 intervals) all total, but then performs the calculation for 16 points (or 15 intervals).--Glenn Cole

#42468: In the bounce method of KeyFrameView.m, you're animating from the current origin of mover's frame. This works well enough so long as the animation isn't interrupted before it can finish -- in this case the origin of mover's frame is constant. But if the animation is interrupted by a subsequent key press, the animation stops and the new origin for the frame is wherever the frame was before the interruption. The origin should be stored after the mover's frame is initialized in the initWithFrame method and that stored value should be used in the bounce method.--Carl Harris

#44267: "Computers are incredibly fast, accurate, and stupid. Human beings are incredibly slow, inaccurate, and brilliant. Together they are powerful beyond imagination."

Does that even sound right? Surely not, do a quick search and you'll find this: benshoemate.com/2008/11/30/einstein-never-said-that/--Christopher Corbettis

#50706: "We will discuss perspective transformations in the section on layers in 3D space."

I consider a "perspective transformations" to be a rotation about the y-axis with a specified vanishing point. This is not discussed -- only pushing it back on the z-axis.--Gordon Apple

#41206: When I ran the Menu Layout Project first mentioned on PDF page 135, each time I pressed the down arrow, the next menu item would get all scrunched up against the previous, so by the end, they were all overlapping in the top of the view.--Sean P. DeNigris

#41207: I got the same error as #41206 for the other two apps in "Layers in 3D" (Platter and Platter 3D Transform)...
"each time I pressed the down arrow, the next menu item would get all scrunched up against the previous, so by the end, they were all overlapping in the top of the view"

Also, the menu options didn't have the effect shown in the figures.--Sean P. DeNigris

#50112: Rashmi,You are essentially tniyrg to measure the user interest in your site, but then you have different kinds of users. I have thought briefly about in another context and here is my half baked thinking this is all theory but am pretty positive this is in right direction Define user segments, you might already have done personas.. in any case.. one way could be publishers, consumers (might be a separate consumer who is download heavy) , by standards/occasional consumersThe goal of each of these guys is different but connected. The publisher's goal would be to offer great content and gain visibility.. so how do you measure if content is great or not one way is star rating, another could be sharing of links by other users (more thinking can draw more ideas), similarly visibility if you track who is getting how much visibility (in terms of views) and then map these two, you'll see how successful are in you in helping publisher achieve her goal.Another matrix you could build on top of this is what I call Zero to Sixty as in acceleration measure (like in cars) is amount of time it takes for someone to visibility, may be that 10% presentations on on slideshare.net reach 10,000 viewership in 30 daysFor consumers they care about quality of content, so you can start taking the above matrix and looking at it at site level and see if the quality of content is improving.The other part with consumers is presentation completion rates how many reached to the end. And second aspect is how much time.. a parallel example to this is market research using online surveys, there are mathematical models available to find outliers (by measuring who run through surveys very quickly etc..). You could explore similar models to see what is the amount of time one should spend on online presentations for it to be valid.These could be interesting stats to include in product blog as well .Similarly with other user segments.. this really tells you how successful your product is in meeting customer needs which will drive business value..The business value in the end will get measured on what parameters affect growth for the business.. is it more people, is it repeating customers, it is amount of new (good quality) content being generated every month etc..- Alok Jain--mmmjOFDRpez