Bug 25170 - Floating point division error
Summary: Floating point division error
Alias: None
Product: iOS
Classification: Xamarin
Component: General ()
Version: XI 8.4.0
Hardware: Macintosh Mac OS
: Normal normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2014-12-09 00:43 UTC by Joseph Hanna
Modified: 2016-03-02 00:07 UTC (History)
4 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Joseph Hanna 2014-12-09 00:43:28 UTC
Description of Problem:

I am getting an exception in my production application on iPad 2 devices but not in iPad Air (both iOS 8.1) for a MT.D table.

Here is the code on row tap:

    var t = root.TableView;
    RectangleF r = t.RectForRowAtIndexPath(t.IndexPathForSelectedRow);

    Debug.WriteLine(string.Format("Tap x:y  {0}", r.ToString()));
    //iPad 2 Returns:    Tap x:y  {X=0,Y=10037,Width=350,Height=63}
    //iPad Air returns:  

    //THIS FOLLOWING LINE CRASHES.  Divide by "2" should produce "int" result
    float yPos = r.Y + float.Parse(int.Parse((r.Height / 2).ToString()).ToString());

This is the exception:

System.FormatException: Input string was not in the correct format
  at System.Int32.Parse (System.String s) [0x00010] in /Developer/MonoTouch/Source/mono/mcs/class/corlib/System/Int32.cs:624 

Steps to reproduce the problem:
1. Run the above code

Actual Results:

This code has been in production for nearly two years.  Only recent release to App Store crashes - on iPad 2 only.

Expected Results:

How often does this happen? 

Every time

Additional Information:

=== Xamarin Studio ===

Version 5.5.4 (build 15)
Installation UUID: 91c8007d-5c08-419d-8255-8baafc57debc
	Mono 3.10.0 ((detached/92c4884)
	GTK+ 2.24.23 (Raleigh theme)

	Package version: 310000031

=== Apple Developer Tools ===

Xcode 6.1.1 (6611)
Build 6A2008a

=== Xamarin.Mac ===

Version: (Business Edition)

=== Xamarin.iOS ===

Version: (Business Edition)
Hash: 840a925
Build date: 2014-11-16 21:03:22-0500

=== Xamarin.Android ===

Version: (Business Edition)
Android SDK: /Users/joe/Library/Developer/Xamarin/android-sdk-mac_x86
	Supported Android versions:
		2.1   (API level 7)
		2.2   (API level 8)
		2.3   (API level 10)
		3.1   (API level 12)
		4.0   (API level 14)
		4.0.3 (API level 15)
Java SDK: /usr
java version "1.6.0_65"
Java(TM) SE Runtime Environment (build 1.6.0_65-b14-466.1-11M4716)
Java HotSpot(TM) 64-Bit Server VM (build 20.65-b04-466.1, mixed mode)

=== Build Information ===

Release ID: 505040015
Git revision: f93940a35458a18052f1a25e106e62ca970d9c40
Build date: 2014-11-19 15:32:41-05
Xamarin addins: dc23cbd91a3a0e1d326328e1229e86c942a49ec8

=== Operating System ===

Mac OS X 10.10.1
Darwin Josephs-MacBook-Pro.local 14.0.0 Darwin Kernel Version 14.0.0
    Fri Sep 19 00:26:44 PDT 2014
    root:xnu-2782.1.97~2/RELEASE_X86_64 x86_64
Comment 1 Rolf Bjarne Kvinge [MSFT] 2014-12-11 02:24:54 UTC
Height = 63 / 2 => 31.5, so your conclusion that that divide by 2 should provide an int result is not correct for this case.

That said, exactly what is the purpose of converting to strings and the parsing?
Comment 2 Joseph Hanna 2016-03-02 00:07:15 UTC
Forget this. Refactored code I want to get it off my list