Windows 10: Why does the string representation of floating-point numbers change after .NET update?

After Windows has updated, some calculated values have changed in the last digit, e.g. from -0.0776529085243926 to -0.0776529085243925. The change is always down by one and both even and odd numbers are affected. This seems to be related to KB4486153, as reverting this update changes the values back to the previous ones. (It may also be related to KB4512192 which was installed at the same time.)

This change can be seen already when debugging in Visual Studio and the value is later written to an output file and changes therein as well (without running the debugger).​

I know about loss of precision in floating-point calculations, but why does this change happen after an update and how can we guarantee that future updates don't change the representation of values?


Minimal reproducible example

The printout below changes from -0.0776529085243926 to -0.0776529085243925 after the update.

var output = -0.07765290852439255;
Trace.WriteLine(output); // This printout changes with the update.

This question was also posted to StackOverflow:

https://stackoverflow.com/questions/57593059/rounding-of-last-digit-changes-after-windows-net-update

:)

 

ordering strings alphanumerically

Hi all

I have a question for you all.

Im trying to order a set of input data. Its a list of strings some containing just number, some just letters and some a mixture. Im coding in c# using i believe asp.net. Its a .net technology. Sorry for the vagueness there but i have only been using it for half a week and my dam windows has died and im writing this from a Ubuntu live cd (gotta love linux).

Any who ive currently managed to split the input list into three seperate list using some regex and converted the numbers into int using int.Parse(). Then ordered the numbers using .order() so that side of things is grand. I now have a list of strings containing just numbers which i order again using .order() and it orders them alphabetically, then using .addrange() i can combine the two together listing all the numbers then all the letters alphabetically at the end. However ive come a bit unstuck with the strings that contain letters and numbers.

for example i have

2test
3test
11test
4ab
1ab
32ab

which i then need listed as

1ab
4ab
32ab
2test
3test
11test

the issue is the number could be on the end or at the front. I want them to be ordered primarely alphabetically then if theres many words starting with T for example they are block together and run numercially.

So when its all finished i end up with a list like this

1
2
5
8
22
32
a
abc
bhg
2bh
bh4
bh5
h
j
3j
j5


Hope all this makes sense im in the process of fixing windows 8 AGAIN so should be able to provide more info if needed. Hope you all can shed some light onto this. Im stuck on ordering the string containing both letters and numbers

 

Intel to Start Shipping B3 Stepping Cougar Point Chipset from February 14

Intel seems to have fast-tracked its Cougar Point chipset flaw rectification. The silicon giant claims that it will be in a position to start shipping B3 stepping of Cougar Point chipsets (Intel P67, H67, etc,) from 14 February, to OEM partners. According to the latest PCN (product change notification), number 110456-00 dated 2/9/2011, Cougar Point B3 will carry the following changes/features:

• Revision ID will change from 04h to 05h
• BIOS Update (Revision 1.1.4 of the BIOS Specification Update and Reference Code)
• B3 stepping package is pin compatible with B2 stepping package
• Minor metal layer change from B2 to B3 improving lifetime wear out with no changes to functionality or design specifications

Of the above, the last bullet point affirms that the SATA 3 Gb/s port defect issue, which caused physical parts of the chipset to wear out abnormally fast, degrading performance, is resolved.

Source: Intel

 

Intel Updates Core 2 Quad Q9550 to E-0 Stepping

We continue our Monday news list with another Intel story that brings to our attention information concerning the company and more specificly its 2.83GHz Core 2 Quad Q9550 chips that will move from the current C-1 to the newer E-0 stepping. The updated chips will start selling on August 22nd, featuring the following changes:

• New SSpec and MM numbers for the converting products
• CPUID will change from 0x10677 to 0x1067A
• Package change to Halide free package

Apart from that, the new stepping CPUs will not include any other changes. Of course, like most new stepping parts a BIOS update will be needed.


Product Change Notification 108663 - 00

Source: TechConnect Magazine