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Wikipedia:Reference desk/Archives/Computing/2014 October 9

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October 9

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Finite State Transducers

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I'm trying to implement the Soundex algorithm as a finite state transducer (yes, it's a piece of homework, but hear me out). We haven't learned how to create composite FSTs. It's obvious that I create small transducers to take care of each step of Soundex, and then put it all together into a big FST, but I really can't figure out how to nest FSTs. Ideally, FST 2 should take FST 1 's output as its input. But how does one do that? I've googled and googled, but nothing's making much sense. Can anyone help me out? You can give a small example and show how you composite two FSTs. Also, I want a diagram (the ones with circles and arrows), not a code implementation. Thank you very much in advance. :) Edit: My biggest problem is that I can't fathom how to 'reset' the pointer. The FST matches/replaces characters and progresses through the string, and when it reaches the final state its pointer points to the last letter in the string, right? So how does someone reset that pointer to go to the first letter of the modified (postprocessed) string? 202.153.41.162 (talk) 11:43, 9 October 2014 (UTC)[reply]

The state space of a composition of FST1 and FST2 will be a subset of all possible (p, q), where p is a state of FST1 and q is a state of FST2. Suppose the composite machine is in state (p, q) and the input symbol is a. You can figure out the next state & output of the embedded FST1 using its transition function. One you have that, you can figure out the next state & output of the embedded FST2 using its transition function, using the output symbol from the embedded FST1 as the input symbol of the embedded FST2. You now have both the next state of the composite machine and its output symbol. — Preceding unsigned comment added by 134.242.92.2 (talk) 19:02, 9 October 2014 (UTC)[reply]

Windows 8 mouse scrolling help needed

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In previous versions of Windows, clicking the scroll wheel placed a little icon at the place where I clicked on the screen, and if I were in a scrollable document, it would allow me to scroll rapidly by moving the cursor: the farther above or below the little icon, the faster it would scroll up or down. In Internet Explorer, this would not happen if I scrollwheelclicked a link — instead, it would bring up a new tab with the URL of the link that I'd just clicked.

I've had my Windows 8.1 computer since late last year, but I use my mouse rarely enough that I've just now observed that this feature has been removed from the default: scrollwheelclicking brings up this weird screen showing the various programs that are running, a graphical display that's redundant to ALT+TAB. What settings can I change to restore normal scrollwheel behavior? I went to Microsoft's website, which had a section on adjusting the scrollwheel settings, saying basically "go into your settings and find the Mouse section, where you can find a subsection for the scrollwheel". I went there and was given a screen that only addresses things like scroll speed and direction, as well as a new Mouse Properties window with a "Wheel" tab that exclusively addresses scroll speed and direction. I don't know where else to look, since Microsoft itself isn't telling me as far as I can tell. My mouse is a Microsoft product, but it's older than the current computer, and it displayed the correct actions when working in Windows 7 a year ago. Nyttend (talk) 12:42, 9 October 2014 (UTC)[reply]

I have Windows 8.1 and just tested IE11; the scroll button works as expected. Try resetting IE: Internet options → Advanced → Reset. --  Gadget850 talk 10:56, 12 October 2014 (UTC)[reply]