2014/10/15 下午 10:04:51

iphone Programming Glossary: calculations

http://stackoverflow.com/questions/10049533/correcting-floating-point-numbers

everything quite appropriately. ex. answer.text NSString stringWithFormat@ g doubleAnswer Using doubles through your calculations and then using that method seemed to work for me and I hope this helps others as well. If this isn't the answer your looking..

Drawing rotated text with NSString drawInRect

http://stackoverflow.com/questions/10289898/drawing-rotated-text-with-nsstring-drawinrect

Optimizing CLLocationManager/CoreLocation to retrieve data points faster on the iPhone

http://stackoverflow.com/questions/1081219/optimizing-cllocationmanager-corelocation-to-retrieve-data-points-faster-on-the

I need to pin point the location of the user as accurately as the device allows without sacrificing too much time. My calculations are darn accurate the problem is it takes far too long to collect 10 samples. I'll paste my filters accuracy respective..

Using custom sections with NSFetchedResultsController?

http://stackoverflow.com/questions/1384345/using-custom-sections-with-nsfetchedresultscontroller

cacheName @ Root Here's where I'm stuck I don't need them sorted by days ago I need them sorted via some calculations based on other attributes in the entity. So I can't just call that custom Category method I need to call a method with arguments..

Double vs float on the iPhone

http://stackoverflow.com/questions/1622729/double-vs-float-on-the-iphone

that regular float. Is this true Evidence I am very interested in the issue because my program needs high precision calculations and I will have to compromise on speed. iphone cocoa touch floating point ieee 754 share improve this question The..

iPhone fluid simulation

http://stackoverflow.com/questions/1784745/iphone-fluid-simulation

not expect the greatest performance when trying to get this working on a mobile device. Running full Navier Stokes calculations on the iPhone is probably going to chug pretty badly. However in the past I was able to perform 2 D fluid modeling simulations.. of simulating fluids even including compressible ones like air. Why this works well on limited hardware is that these calculations can be done using bitwise operators and simple lookup tables without the need for any floating point calculations. You might.. calculations can be done using bitwise operators and simple lookup tables without the need for any floating point calculations. You might be able to make something like this work on the iPhone's processor. For more on this technique you can consult..

Measuring velocity via iPhone SDK

http://stackoverflow.com/questions/1994018/measuring-velocity-via-iphone-sdk

accel decel tend to lag very badly from a user interaction standpoint. Also I need to feed velocity into some other calculations that I'm doing and the precision is not really what I need. It seems possible based on very few other apps I've seen notably..

UIButton: how to center an image and a text using imageEdgeInsets and titleEdgeInsets?

http://stackoverflow.com/questions/2451223/uibutton-how-to-center-an-image-and-a-text-using-imageedgeinsets-and-titleedgei

the image never gets centered because appears that it is dependent of the button.titleLabel size. I already tried many calculations with button size image size titleLabel size and never get both perfectly centered. Someone already have the same problem..

“Incorrect” frame / window size after re-orientation in iPhone

http://stackoverflow.com/questions/2686882/incorrect-frame-window-size-after-re-orientation-in-iphone

How do you use NSAttributedString?

http://stackoverflow.com/questions/3482346/how-do-you-use-nsattributedstring

length of each of the three NSAttributedString substrings will be changing often and so I would prefer not to use any calculations to re position 3 separate NSString objects. If it's possible using NSAttributedString how do I make the following if not..

Is there a way to make drawRect work right NOW?

http://stackoverflow.com/questions/4739748/is-there-a-way-to-make-drawrect-work-right-now

loop. These updates are performed on the main thread so anything that runs for a long time in the main thread lengthy calculations etc. will prevent the interface updates from being started. Additionally anything that runs for a while on the main thread..

Iphone - when to calculate heightForRowAtIndexPath for a tableview when each cell height is dynamic?

http://stackoverflow.com/questions/4823197/iphone-when-to-calculate-heightforrowatindexpath-for-a-tableview-when-each-cel

because cellForRowAtIndexPath is called AFTER heightForRowAtIndexPath. The only thing I can think of is to do all the calculations inside viewDidLoad create all the UITableViewCells then calculate the cells height and store that in a custom field inside.. because they hold varying amounts of text you can use one of the sizeWithFont methods on the relevant string to do the calculations. This is quicker than building a view and then measuring the result. Note that if you change the height of a cell you will..

problem with collision of two images

http://stackoverflow.com/questions/5926355/problem-with-collision-of-two-images

I didn't even know how to write a decent game loop. You will need that first because you need to do precise time step calculations. AFA the collisions you update your model and view separately so if you update the model and objects overlap you need to..

UITableView and keyboard scrolling issue

http://stackoverflow.com/questions/594181/uitableview-and-keyboard-scrolling-issue

Calculate new coordinate x meters and y degree away from one coordinate

http://stackoverflow.com/questions/6633850/calculate-new-coordinate-x-meters-and-y-degree-away-from-one-coordinate

Unfortunately there's no such function provided in the api so you'll have to write your own. This site gives several calculations involving latitude longitude and sample JavaScript code. Specifically the section titled Destination point given distance..

How to lose margin/padding in UITextView?

http://stackoverflow.com/questions/746670/how-to-lose-margin-padding-in-uitextview

using the offset margin parameter of the UITextView . My problem is that the padding of the UITextView is confusing my calculations as it seems to be different depending on the font size and typeface that I use. Therefore I pose the question Is it possible..