2014/10/15 下午 10:14:23

iphone Programming Glossary: sqrt

http://stackoverflow.com/questions/12091916/uiview-with-a-dashed-line

CALayer layer CGPoint a CGPoint b CGFloat lineWidth CGPoint center 0.5 a.x b.x 0.5 a.y b.y CGFloat length sqrt a.x b.x a.x b.x a.y b.y a.y b.y CGFloat angle atan2 a.y b.y a.x b.x layer.position center layer.bounds CGRect 0 0 length..

how to calculate two coordinates distance in objective c?

http://stackoverflow.com/questions/1980898/how-to-calculate-two-coordinates-distance-in-objective-c

rad lat1 double radLat2 self rad lat2 double a radLat1 radLat2 double b self rad lng1 self rad lng2 double s 2 asin sqrt pow sin a 2 2 cos radLat1 cos radLat2 pow sin b 2 2 s s EARTH_RADIUS s round s 10000 10000 return s double rad double d..

How to detect iPhone movement in space using accelerometer?

http://stackoverflow.com/questions/2674717/how-to-detect-iphone-movement-in-space-using-accelerometer

1.0 kFileringFactor gravity.z currentAcceleration.z kFileringFactor gravity.z 1.0 kFileringFactor float gravityNorm sqrt gravity.x gravity.x gravity.y gravity.y gravity.z gravity.z Removing gravity vector from initial acceleration filteredAcceleration.x..

Cumulative Normal Distribution function in objective C

http://stackoverflow.com/questions/2785944/cumulative-normal-distribution-function-in-objective-c

variance 1 you'll need to use the appropriate scaling so for some mean and variance it will be return 0.5 erfc mean x sqrt variance M_SQRT1_2 If you don't need double precision change the doubles to floats use the erfcf function and change the..

App Crashing when using large images on iOS 4.0

http://stackoverflow.com/questions/3679457/app-crashing-when-using-large-images-on-ios-4-0

the image size to MAX_PIXELS float actualHeight image.size.height float actualWidth image.size.width float scale sqrt image.size.width image.size.height MAX_PIXELS resize the image CGRect rect CGRectMake 0.0 0.0 floorf actualWidth scale floorf..

UISwipeGestureRecognizer Swipe length

http://stackoverflow.com/questions/4828833/uiswipegesturerecognizer-swipe-length

What's the best approach to draw lines between views?

http://stackoverflow.com/questions/5847876/whats-the-best-approach-to-draw-lines-between-views

Applying Zoom Effect In cocos2D gaming environment?

http://stackoverflow.com/questions/5919180/applying-zoom-effect-in-cocos2d-gaming-environment

previousLocationInView touchTwo view Get the distance for the current and previous touches. CGFloat currentDistance sqrt pow touchLocationOne.x touchLocationTwo.x 2.0f pow touchLocationOne.y touchLocationTwo.y 2.0f CGFloat previousDistance.. touchLocationOne.x touchLocationTwo.x 2.0f pow touchLocationOne.y touchLocationTwo.y 2.0f CGFloat previousDistance sqrt pow previousLocationOne.x previousLocationTwo.x 2.0f pow previousLocationOne.y previousLocationTwo.y 2.0f Get the delta..

How can I improve the performance of my custom OpenGL ES 2.0 depth texture generation?

http://stackoverflow.com/questions/6051237/how-can-i-improve-the-performance-of-my-custom-opengl-es-2-0-depth-texture-gener

length impostorSpaceCoordinate if distanceFromCenter 1.0 gl_FragColor vec4 1.0 else float calculatedDepth sqrt 1.0 distanceFromCenter distanceFromCenter mediump float currentDepthValue normalizedDepth adjustedSphereRadius calculatedDepth.. To do this I enable depth testing and then draw out the squares that make up the objects in my scene shrunken by sqrt 2 2 with a simple opaque shader. This will create inset squares covering area known to be opaque in a represented sphere...

iPhone FFT with Accelerate framework vDSP

http://stackoverflow.com/questions/6358764/iphone-fft-with-accelerate-framework-vdsp

the imaginary part. If you are just interested in the magnitude of each bin in the frequency domain then you calculate sqrt re re im im for each output bin. If you're only interested in relative magnitude then you can drop the sqrt and just calculate.. calculate sqrt re re im im for each output bin. If you're only interested in relative magnitude then you can drop the sqrt and just calculate the squared magnitude re re im im . You would look at the magnitudes of the bin or bins see 2 that correspond..

Need to find Distance using Gyro+Accelerometer

http://stackoverflow.com/questions/6647314/need-to-find-distance-using-gyroaccelerometer

from start to end of measurement at times 0 dt 2 dt 3 dt ... n 1 dt. To find the total displacement you just do dl sqrt dx dx dy dy dz dz Gyroscope is not necessary for this but if you are measuring linear distances you can use the gyroscope..

Using UIPinchGestureRecognizer to scale uiviews in single direction

http://stackoverflow.com/questions/6759028/using-uipinchgesturerecognizer-to-scale-uiviews-in-single-direction

currentTouchLocation andPoint2 lastTouchPosition NSLog @ deltaMove @ NSStringFromCGPoint deltaMove float distance sqrt deltaMove.x deltaMove.x deltaMove.y deltaMove.y NSLog @ distance f distance float hScale 1 deltaMove.x distance 1 gestureRecognizer.scale.. locationInView yourViewHere CGPoint deltaMove CGPointDistance currentTouchLocation lastTouchPosition float distance sqrt deltaMove.x deltaMove.x deltaMove.y deltaMove.y hScale abs deltaMove.x distance 1 gestureRecognizer.scale vScale abs deltaMove.y.. locationInView yourViewHere CGPoint deltaMove CGPointDistance currentTouchLocation lastTouchPosition float distance sqrt deltaMove.x deltaMove.x deltaMove.y deltaMove.y float hScale 1 abs deltaMove.x distance 1 gestureRecognizer.scale float..

Help calculating X and Y from Latitude and Longitude in iPhone

http://stackoverflow.com/questions/6852195/help-calculating-x-and-y-from-latitude-and-longitude-in-iphone

space via equirectangular projection p1 lonp lon1 cos 0.5 latp lat1 convert lat lon to radians p2 latp lat1 distance R sqrt p1 p1 p2 p2 use R 6371000 and your distance will be in meters Now scale this distance to your map scale At this point you..