# šŸ“š Official Books **URL:** https://forums.kodeco.com/c/books/6.md?page=110 [Latest](https://forums.kodeco.com/latest.md) Ā· [Categories](https://forums.kodeco.com/categories.md) Ā· [Tags](https://forums.kodeco.com/tags.md) **Page:** 111 --- ## [Tutorial Beginning Machine Learning with scikit-learn](https://forums.kodeco.com/t/tutorial-beginning-machine-learning-with-scikit-learn/51892)
**Author:** [@faabalia](https://forums.kodeco.com/u/faabalia)\ **Replies:** 2\ **Last updated:** [October 16, 2018, 1:18pm UTC](https://forums.kodeco.com/t/tutorial-beginning-machine-learning-with-scikit-learn/51892 "2018-10-16T13:18:49Z")
Hi, I have done the tutorial, now I am trying to build a Lasso model: from sklearn import linear\_model reg = linear\_model.Lasso(alpha = 0.1) reg.fit(X\_train, y\_train) reg.score(X\_test, y\_test) All this I have done ā€¦ --- ## [CHh 16 particles](https://forums.kodeco.com/t/chh-16-particles/52948)
**Author:** [@bababoega](https://forums.kodeco.com/u/bababoega)\ **Replies:** 2\ **Last updated:** [October 16, 2018, 12:17pm UTC](https://forums.kodeco.com/t/chh-16-particles/52948 "2018-10-16T12:17:18Z")
In chapter 16 when trying the premade fire particle emitter for the first time. The particles should automatically (by premade code) scaling down as they move up the screen. However the size of the particles stays the saā€¦ --- ## [GPU hangs when rendering with two render encoders?](https://forums.kodeco.com/t/gpu-hangs-when-rendering-with-two-render-encoders/52851)
**Author:** [@dormouse](https://forums.kodeco.com/u/dormouse)\ **Replies:** 6\ **Last updated:** [October 15, 2018, 1:20pm UTC](https://forums.kodeco.com/t/gpu-hangs-when-rendering-with-two-render-encoders/52851 "2018-10-15T13:20:00Z")
Hello! Iā€™m trying to make use of G-buffer in my project and Iā€™m using a project from Chapter 14 as a reference. For some reason GPU hangs for about 5 seconds if I try to render composition quad in a separate pass, and coā€¦ --- ## [Music and sound effects stop working after several stages](https://forums.kodeco.com/t/music-and-sound-effects-stop-working-after-several-stages/47678)
**Author:** [@chrismtorio](https://forums.kodeco.com/u/chrismtorio)\ **Replies:** 1\ **Last updated:** [October 14, 2018, 9:58am UTC](https://forums.kodeco.com/t/music-and-sound-effects-stop-working-after-several-stages/47678 "2018-10-14T09:58:48Z")
Iā€™m currenlty using the 2D iOS & tvOS Games by tutorial as my go to reference for my upcoming game. After several stages, some of the sound effects and the background theme stop working. Iā€™m using AVAudioPlayer for my ā€¦ --- ## [Code Error in Asynchronous fetching of Chapter 4](https://forums.kodeco.com/t/code-error-in-asynchronous-fetching-of-chapter-4/52779)
**Author:** [@thammaporn](https://forums.kodeco.com/u/thammaporn)\ **Replies:** 2\ **Last updated:** [October 14, 2018, 5:26am UTC](https://forums.kodeco.com/t/code-error-in-asynchronous-fetching-of-chapter-4/52779 "2018-10-14T05:26:02Z")
Hello , I have trouble with the code following by tutorial core data regarding Asynchronous fetching in Chapter 4 as below snapshot . Appriciated if you could help. Thank you. --- ## [Clear texture crash](https://forums.kodeco.com/t/clear-texture-crash/52665)
**Author:** [@monkyu](https://forums.kodeco.com/u/monkyu)\ **Replies:** 1\ **Last updated:** [October 12, 2018, 5:02am UTC](https://forums.kodeco.com/t/clear-texture-crash/52665 "2018-10-12T05:02:24Z")
I was meeting a problem when I try to clear the texture content use the method: attention: the autoResizeDrawable is true CGSize blankSize = CGSizeMake(self.bounds.size.width, self.bounds.size.height); self.region = ā€¦ --- ## [No "Keys" option in the Member Center](https://forums.kodeco.com/t/no-keys-option-in-the-member-center/52612)
**Author:** [@drg](https://forums.kodeco.com/u/drg)\ **Replies:** 2\ **Last updated:** [October 11, 2018, 6:52pm UTC](https://forums.kodeco.com/t/no-keys-option-in-the-member-center/52612 "2018-10-11T18:52:39Z")
Good morning. Iā€™m starting chapter 5, but when I try to follow the instructions, I cannot find the ā€œKeysā€ option in the Member Center. What would be an alternate way to add the key? The instructions said: ā€œGetting youā€¦ --- ## [Chapter 15, animating plane with rotation mode](https://forums.kodeco.com/t/chapter-15-animating-plane-with-rotation-mode/39489)
**Author:** [@bpashch](https://forums.kodeco.com/u/bpashch)\ **Replies:** 2\ **Last updated:** [October 10, 2018, 2:38pm UTC](https://forums.kodeco.com/t/chapter-15-animating-plane-with-rotation-mode/39489 "2018-10-10T14:38:17Z")
Hey There! :\] As itā€™s mentioned suggested the book, Iā€™m trying to practice rotationMode: If youā€™re going to create more complex path animations and want to stay sane, youā€™d do well to keep in mind the note about rotatā€¦ --- ## [RxSwift book 2nd - Chapter 23 project not building](https://forums.kodeco.com/t/rxswift-book-2nd-chapter-23-project-not-building/52443)
**Author:** [@dmullaraj](https://forums.kodeco.com/u/dmullaraj)\ **Replies:** 1\ **Last updated:** [October 10, 2018, 1:49pm UTC](https://forums.kodeco.com/t/rxswift-book-2nd-chapter-23-project-not-building/52443 "2018-10-10T13:49:11Z")
Hello, I am in chapter 23, after getting the initial project ā€œTweetieā€ I did pod install, open the project everything seems fine. I Run/Build the project with iPhone 8 and gave me lots of errors. Canā€™t either build it ā€¦ --- ## [Chapter 15 semaphore issue?](https://forums.kodeco.com/t/chapter-15-semaphore-issue/52407)
**Author:** [@zzyzy](https://forums.kodeco.com/u/zzyzy)\ **Replies:** 7\ **Last updated:** [October 10, 2018, 5:03am UTC](https://forums.kodeco.com/t/chapter-15-semaphore-issue/52407 "2018-10-10T05:03:16Z")
First question: Concerning the Renderer ā€œdrawā€ routine in Chap 15 of Metal Tutorials, beginning with a semaphore.wait. Iā€™m looking more at the sample code than the book. (The only mentions of semaphore in the book areā€¦ --- ## [Errors and Issues with raywenderlich's Final Version of Headlines app](https://forums.kodeco.com/t/errors-and-issues-with-raywenderlichs-final-version-of-headlines-app/44450)
**Author:** [@ayl0918](https://forums.kodeco.com/u/ayl0918)\ **Replies:** 5\ **Last updated:** [October 9, 2018, 9:35pm UTC](https://forums.kodeco.com/t/errors-and-issues-with-raywenderlichs-final-version-of-headlines-app/44450 "2018-10-09T21:35:02Z")
I was testing with the Headlines app that I had completed from the starter version, but the completed app still crash and other issues with some of the news sources. So I went and tested the final version of Headlines aā€¦ --- ## [Metal, V1.0 Missing Chapters 1-3](https://forums.kodeco.com/t/metal-v1-0-missing-chapters-1-3/52264)
**Author:** [@billcod](https://forums.kodeco.com/u/billcod)\ **Replies:** 2\ **Last updated:** [October 9, 2018, 11:57am UTC](https://forums.kodeco.com/t/metal-v1-0-missing-chapters-1-3/52264 "2018-10-09T11:57:28Z")
I just upgraded to the new full release of Metal, and it seems to be missing Chapters 1-3 in the files. I just saved the ones from the previous release, but you might check this out. Thanks. --- ## [Cannot download the book: error 404](https://forums.kodeco.com/t/cannot-download-the-book-error-404/52136)
**Author:** [@jdmuys](https://forums.kodeco.com/u/jdmuys)\ **Replies:** 3\ **Last updated:** [October 8, 2018, 7:53am UTC](https://forums.kodeco.com/t/cannot-download-the-book-error-404/52136 "2018-10-08T07:53:31Z")
The official page at https://store.raywenderlich.com/products/rxswift, which is linked from the book information page, as well as from my account page which shows my purchases, is missing. If I try that URL, I get a misā€¦ --- ## [CH8 - Tooling Section](https://forums.kodeco.com/t/ch8-tooling-section/52055)
**Author:** [@jpatrickmc](https://forums.kodeco.com/u/jpatrickmc)\ **Replies:** 1\ **Last updated:** [October 6, 2018, 6:08pm UTC](https://forums.kodeco.com/t/ch8-tooling-section/52055 "2018-10-06T18:08:09Z")
The text states ā€œFlashCardsTooling defines the TOOLING environment variable so you donā€™t need to do that yourself.ā€ I could be overlooking, but where and how is that set by FlashCardsTooling? --- ## [Where is the pdf standalone file?](https://forums.kodeco.com/t/where-is-the-pdf-standalone-file/51445)
**Author:** [@smashkins](https://forums.kodeco.com/u/smashkins)\ **Replies:** 1\ **Last updated:** [October 3, 2018, 6:24pm UTC](https://forums.kodeco.com/t/where-is-the-pdf-standalone-file/51445 "2018-10-03T18:24:56Z")
I purchased the book but the pdf version in only inside the all book & project files and not as a separated file. --- ## [Where to get good introduction to machine learning?](https://forums.kodeco.com/t/where-to-get-good-introduction-to-machine-learning/50148)
**Author:** [@bkw](https://forums.kodeco.com/u/bkw)\ **Replies:** 2\ **Last updated:** [October 1, 2018, 8:39pm UTC](https://forums.kodeco.com/t/where-to-get-good-introduction-to-machine-learning/50148 "2018-10-01T20:39:42Z")
Hi. Since Chapter 1 is not available yet, what do you recommend I read to get a good introduction or overview of Machine Learning? --- ## [Making a Vapor App with different profiles](https://forums.kodeco.com/t/making-a-vapor-app-with-different-profiles/51312)
**Author:** [@frasco](https://forums.kodeco.com/u/frasco)\ **Replies:** 2\ **Last updated:** [October 1, 2018, 2:20pm UTC](https://forums.kodeco.com/t/making-a-vapor-app-with-different-profiles/51312 "2018-10-01T14:20:17Z")
Hello, Iā€™m doing a Steam application to manage school sports. Each user of this application has an assigned role and based on his profile he will see one section or another. Whats the better option to do this? Iā€™m thinā€¦ --- ## [Chapter 13 - Extend UIKit views using MKMapView (v2.0](https://forums.kodeco.com/t/chapter-13-extend-uikit-views-using-mkmapview-v2-0/39494)
**Author:** [@barrera](https://forums.kodeco.com/u/barrera)\ **Replies:** 1\ **Last updated:** [October 1, 2018, 1:07pm UTC](https://forums.kodeco.com/t/chapter-13-extend-uikit-views-using-mkmapview-v2-0/39494 "2018-10-01T13:07:00Z")
The code to create the delegate proxy doesnā€™t correspond to extend MKMapView, itā€™s the code for the CLLocationManager. --- ## [Chapter 12, Page 266 - Keyboard not displaying on iPad mini](https://forums.kodeco.com/t/chapter-12-page-266-keyboard-not-displaying-on-ipad-mini/40150)
**Author:** [@iosimago](https://forums.kodeco.com/u/iosimago)\ **Replies:** 3\ **Last updated:** [October 1, 2018, 1:05pm UTC](https://forums.kodeco.com/t/chapter-12-page-266-keyboard-not-displaying-on-ipad-mini/40150 "2018-10-01T13:05:06Z")
Hello, Iā€™m running the app and when I tap on the cell, the keyboard doesnā€™t display on the iPad mini. Is this a bug? thanks --- ## [P. 42: Where's the Attributes Inspector?](https://forums.kodeco.com/t/p-42-wheres-the-attributes-inspector/39991)
**Author:** [@7stud](https://forums.kodeco.com/u/7stud)\ **Replies:** 2\ **Last updated:** [October 1, 2018, 1:00pm UTC](https://forums.kodeco.com/t/p-42-wheres-the-attributes-inspector/39991 "2018-10-01T13:00:52Z")
Xcode 9.2 Core Data by Tutorial v4.0.1 p. 42 This is what Iā€™m seeing: --- ## [Chapter 23 - ā€žAdding a View Model testā€œ (errata)](https://forums.kodeco.com/t/chapter-23-adding-a-view-model-test-errata/40885)
**Author:** [@rabe](https://forums.kodeco.com/u/rabe)\ **Replies:** 1\ **Last updated:** [October 1, 2018, 12:54pm UTC](https://forums.kodeco.com/t/chapter-23-adding-a-view-model-test-errata/40885 "2018-10-01T12:54:26Z")
To get a array of type \[Event\] for the emitted variable I had (instead of) let loggedIn = viewModel.loggedIn.asObservable() do this. let loggedIn = viewModel.loggedIn.asObservable().materialize() --- ## [Chapter 23 - Challenges (errata)](https://forums.kodeco.com/t/chapter-23-challenges-errata/40953)
**Author:** [@rabe](https://forums.kodeco.com/u/rabe)\ **Replies:** 1\ **Last updated:** [October 1, 2018, 12:49pm UTC](https://forums.kodeco.com/t/chapter-23-challenges-errata/40953 "2018-10-01T12:49:37Z")
Iā€™ve seen that if you wait for the next pull for new tweets (after timeDelay) Tweetie crashes with (Error.duplicateItem(item: item) in Diff.swift from Differentiator. Could work around the problem by changing the code iā€¦ --- ## [Dates of new releases](https://forums.kodeco.com/t/dates-of-new-releases/50914)
**Author:** [@faabalia](https://forums.kodeco.com/u/faabalia)\ **Replies:** 2\ **Last updated:** [October 1, 2018, 7:23am UTC](https://forums.kodeco.com/t/dates-of-new-releases/50914 "2018-10-01T07:23:47Z")
Hi, I have bought the early release. When is predicted more or less a new release with more chapters? Greetings, Felix. --- ## [Interactive UIViewPropertyAnimator + UIView.transitions](https://forums.kodeco.com/t/interactive-uiviewpropertyanimator-uiview-transitions/47050)
**Author:** [@fespinozacast](https://forums.kodeco.com/u/fespinozacast)\ **Replies:** 2\ **Last updated:** [October 1, 2018, 7:01am UTC](https://forums.kodeco.com/t/interactive-uiviewpropertyanimator-uiview-transitions/47050 "2018-10-01T07:01:46Z")
Hi, There is an example in the book (Chapter 21, Built-in view transitions), on which a UIView.transition(with call is used inside a UIViewPropertyAnimator instance, but this doesnā€™t seem to work when trying to drive thā€¦ --- ## [TableView keyboard done button does not add item](https://forums.kodeco.com/t/tableview-keyboard-done-button-does-not-add-item/51325)
**Author:** [@harryballas](https://forums.kodeco.com/u/harryballas)\ **Replies:** 2\ **Last updated:** [October 1, 2018, 4:20am UTC](https://forums.kodeco.com/t/tableview-keyboard-done-button-does-not-add-item/51325 "2018-10-01T04:20:28Z")
I have been following along with the tutorial about tableviews online, and when I go to the add item screen the done bar button adds the item to the checklist view controller, however the done button on the keyboard onlyā€¦ --- ## [Bug in Ch15 final project: Custom pull-to-refresh view drifts under certain circumstances](https://forums.kodeco.com/t/bug-in-ch15-final-project-custom-pull-to-refresh-view-drifts-under-certain-circumstances/26162)
**Author:** [@alijaza](https://forums.kodeco.com/u/alijaza)\ **Replies:** 1\ **Last updated:** [October 1, 2018, 2:53am UTC](https://forums.kodeco.com/t/bug-in-ch15-final-project-custom-pull-to-refresh-view-drifts-under-certain-circumstances/26162 "2018-10-01T02:53:48Z")
I noticed an annoying bug in the final demo project for this chapter. You can see from this gif that there is a bit of continuing deceleration after releasing the refresh trigger: Afā€¦ --- ## [Added audio and now hero doesn't appear](https://forums.kodeco.com/t/added-audio-and-now-hero-doesnt-appear/50175)
**Author:** [@darthcolejoy](https://forums.kodeco.com/u/darthcolejoy)\ **Replies:** 6\ **Last updated:** [October 1, 2018, 2:37am UTC](https://forums.kodeco.com/t/added-audio-and-now-hero-doesnt-appear/50175 "2018-10-01T02:37:31Z")
Hi, I have gotten to the audio chapter and added some audio to the game. The background music worked fine but now when I have added the SFX and play the game - my hero doesnā€™t appear on the scene. How can I upload my pā€¦ --- ## [Animation doesn't work when I apply autolayout before the running?](https://forums.kodeco.com/t/animation-doesnt-work-when-i-apply-autolayout-before-the-running/44090)
**Author:** [@agung](https://forums.kodeco.com/u/agung)\ **Replies:** 1\ **Last updated:** [October 1, 2018, 2:14am UTC](https://forums.kodeco.com/t/animation-doesnt-work-when-i-apply-autolayout-before-the-running/44090 "2018-10-01T02:14:01Z")
I just start to read this ebook, and after reading to chapter 2, I want to implement it to my own project, but ā€˜something weirdā€™ happens. so let say I have a button. and I implement autolayout before the running. I makeā€¦ --- ## [Video quality issues](https://forums.kodeco.com/t/video-quality-issues/14751)
**Author:** [@lajosdavid](https://forums.kodeco.com/u/lajosdavid)\ **Replies:** 3\ **Last updated:** [October 1, 2018, 1:57am UTC](https://forums.kodeco.com/t/video-quality-issues/14751 "2018-10-01T01:57:14Z")
Hi, I have quality issues during the videos. Itā€™s not continuous, but sometimes itā€™s quality is really bad, texts are unreadable. I set the quality manually to 1080p, but itā€™s the same. Example: (Session 102) Good: ā€¦ --- ## [Syntax Explanation Please](https://forums.kodeco.com/t/syntax-explanation-please/51342)
**Author:** [@jinkazama](https://forums.kodeco.com/u/jinkazama)\ **Replies:** 2\ **Last updated:** [October 1, 2018, 12:29am UTC](https://forums.kodeco.com/t/syntax-explanation-please/51342 "2018-10-01T00:29:53Z")
on page 189, the code for structure seems to be a bit strange to me. After I checked the code to implement the tic-tac-toe game, there is a line of code that looks like this: // Return true if all the board positions aā€¦ [Previous page](https://forums.kodeco.com/c/books/6.md?page=109) [Next page](https://forums.kodeco.com/c/books/6.md?page=111)