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  • How to Use border as an image in android xml

    - by Ethan Hunt
    I have a popup to show in my xml. It should have a border. Following is the code:- <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/rl_parent" android:layout_width="wrap_content" android:layout_height="wrap_content" android:paddingBottom="20dp" > <RelativeLayout android:id="@+id/rl_startpopup" android:layout_width="340dp" android:layout_height="320dp" android:layout_marginLeft="10dp" android:layout_marginRight="10dp" android:background="@drawable/popup_outline" android:orientation="vertical" /> </RelativeLayout> The popup_outline is a shape <?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle" > <gradient android:angle="270" android:endColor="#192423" android:startColor="#4a7669" android:type="linear" /> <corners android:radius="8dp" /> <stroke android:width="2dp" android:color="#e4f4d3" /> </shape> here is the image of the popup:- This "popup_outline" is the white border shown. I want to use a repeatable pattern image instead of one color as the border. I have to do this in xml. Please help

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  • Android: Capturing the return of an activity.

    - by Chrispix
    I have a question regarding launching new activities. It boils down to this. I have 3 tabs on a view A) contains gMap activity B) camera activity C) some random text fields. Requirement is that the application runs in Portrait mode. All 3 tabs work as expected w/ the exception of the Camera Preview Surface (B). It is rotated 90 degrees. They only way to make it correct is to set the app to landscape which throws all my tabs around, and is pretty much unworkable. My solution is this : replace my camera activity with a regular activity that is empty w/ the exception of Intent i = new Intent(this,CameraActivity.class); startActivity(i); This launches my CameraActivity. And that works fine. I had to do a linear layout and include 3 images that look like real tabs, so I can try and mimic the operation of the tabs while rotating the screen to landscape and keep the visuals as portrait. The user can click one of the images(buttons) to display the next tab. This is my issue. It should exit my 'camera activity' returning to the 'blank activity' in a tab, where it should be interpreted to click the desiered tab from my image. The main thing is, when it returns, it returns to a blank (black) page under a tab (because it is 'empty'). How can I capture the return event back to the page that called the activity, and then see what action they performed? I can set an onclicklistener where I can respond to the fake tabs (images) being clicked to exit out of the camera activity. On exit, the tab should update so that is where you return. any Suggestions? Thanks,

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  • Interpolating data points in Excel

    - by Niels Basjes
    Hi, I'm sure this is the kind of problem other have solved many times before. A group of people are going to do measurements (Home energy usage to be exact). All of them will do that at different times and in different intervals. So what I'll get from each person is a set of {date, value} pairs where there are dates missing in the set. What I need is a complete set of {date, value} pairs where for each date withing the range a value is known (either measured or calculated). I expect that a simple linear interpolation would suffice for this project. If I assume that it must be done in Excel. What is the best way to interpolate in such a dataset (so I have a value for every day) ? Thanks. NOTE: When these datasets are complete I'll determine the slope (i.e. usage per day) and from that we can start doing home-to-home comparisons. ADDITIONAL INFO After first few suggestions: I do not want to manually figure out where the holes are in my measurement set (too many incomplete measurement sets!!). I'm looking for something (existing) automatic to do that for me. So if my input is {2009-06-01, 10} {2009-06-03, 20} {2009-06-06, 110} Then I expect to automatically get {2009-06-01, 10} {2009-06-02, 15} {2009-06-03, 20} {2009-06-04, 50} {2009-06-05, 80} {2009-06-06, 110} Yes, I can write software that does this. I am just hoping that someone already has a "ready to run" software (Excel) feature for this (rather generic) problem.

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  • Update graph in real time from server

    - by user1869421
    I'm trying to update a graph with received data, so that the height of the bars increase as more data is received from the server via a websocket. But my code doesn't render a graph in the browser and plot the data points. I cannot see anything wrong with the code. I really need some help here please. ws = new WebSocket("ws://localhost:8888/dh"); var useData = [] //var chart; var chart = d3.select("body") .append("svg:svg") .attr("class", "chart") .attr("width", 420) .attr("height", 200); ws.onmessage = function(evt) { var distances = JSON.parse(evt.data); data = distances.miles; console.log(data); if(useData.length <= 10){ useData.push(data) } else { var draw = function(data){ // Set the width relative to max data value var x = d3.scale.linear() .domain([0, d3.max(useData)]) .range([0, 420]); var y = d3.scale.ordinal() .domain(useData) .rangeBands([0, 120]); var rect = chart.selectAll("rect") .data(useData) // enter rect rect.enter().append("svg:rect") .attr("y", y) .attr("width", x) .attr("height", y.rangeBand()); // update rect rect .attr("y", y) .attr("width", x) .attr("height", y.rangeBand()); var text = chart.selectAll("text") .data(useData) // enter text text.enter().append("svg:text") .attr("x", x) .attr("y", function (d) { return y(d) + y.rangeBand() / 2; }) .attr("dx", -3) // padding-right .attr("dy", ".35em") // vertical-align: middle .attr("text-anchor", "end") // text-align: right .text(String); // update text text .data(useData) .attr("x", x) .text(String); } useData.length = 0; } } Thanks

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  • Parallel.For Batching

    - by chibacity
    Is there built-in support in the TPL for batching operations? I was recently playing with a routine to carry out character replacement on a character array which required a lookup table i.e. transliteration: for (int i = 0; i < chars.Length; i++) { char replaceChar; if (lookup.TryGetValue(chars[i], out replaceChar)) { chars[i] = replaceChar; } } I could see that this could be trivially parallelized, so jumped in with a first stab which I knew would perform worse as the tasks were too fine-grained: Parallel.For(0, chars.Length, i => { char replaceChar; if (lookup.TryGetValue(chars[i], out replaceChar)) { chars[i] = replaceChar; } }); I then reworked the algorithm to use batching so that the work could be chunked onto different threads in less fine-grained batches. This made use of threads as expected and I got some near linear speed up. I'm sure that there must be built-in support for batching in the TPL. What is the syntax, and how do I use it? const int CharBatch = 100; int charLen = chars.Length; Parallel.For(0, ((charLen / CharBatch) + 1), i => { int batchUpper = ((i + 1) * CharBatch); for (int j = i * CharBatch; j < batchUpper && j < charLen; j++) { char replaceChar; if (lookup.TryGetValue(chars[j], out replaceChar)) { chars[j] = replaceChar; } } });

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  • What limits scaling in this simple OpenMP program?

    - by Douglas B. Staple
    I'm trying to understand limits to parallelization on a 48-core system (4xAMD Opteron 6348, 2.8 Ghz, 12 cores per CPU). I wrote this tiny OpenMP code to test the speedup in what I thought would be the best possible situation (the task is embarrassingly parallel): // Compile with: gcc scaling.c -std=c99 -fopenmp -O3 #include <stdio.h> #include <stdint.h> int main(){ const uint64_t umin=1; const uint64_t umax=10000000000LL; double sum=0.; #pragma omp parallel for reduction(+:sum) for(uint64_t u=umin; u<umax; u++) sum+=1./u/u; printf("%e\n", sum); } I was surprised to find that the scaling is highly nonlinear. It takes about 2.9s for the code to run with 48 threads, 3.1s with 36 threads, 3.7s with 24 threads, 4.9s with 12 threads, and 57s for the code to run with 1 thread. Unfortunately I have to say that there is one process running on the computer using 100% of one core, so that might be affecting it. It's not my process, so I can't end it to test the difference, but somehow I doubt that's making the difference between a 19~20x speedup and the ideal 48x speedup. To make sure it wasn't an OpenMP issue, I ran two copies of the program at the same time with 24 threads each (one with umin=1, umax=5000000000, and the other with umin=5000000000, umax=10000000000). In that case both copies of the program finish after 2.9s, so it's exactly the same as running 48 threads with a single instance of the program. What's preventing linear scaling with this simple program?

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  • Custom android preference type loses focus when typing

    - by Brian
    I created a simple preference class that shows an AutoCompleteTextView control and it displays properly but when i focus on the AutoCompleteTextView and start typing it brings up the keyboard but then immediately loses focus on the control. Any idea why this loses focus? Here's what i did to create the view. the inflated layout is just a basic linear layout with a title textview in it. I could change it to a dialog preference instead I guess but it'd be smoother if it could be part of the base view. @Override protected View onCreateView(ViewGroup parent) { LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE); LinearLayout layout = (LinearLayout) inflater.inflate(R.layout.base_preference, null); if (mHint != null) { TextView hintView = (TextView) layout.findViewById(R.id.PreferenceHintTextView); hintView.setText(mHint); } TextView titleView = (TextView) layout.findViewById(R.id.PreferenceTitleTextView); titleView.setText(getTitle()); AutoCompleteTextView inputView = new AutoCompleteTextView(getContext()); inputView.setGravity(Gravity.FILL_HORIZONTAL); ArrayAdapter<CharSequence> adapter = new ArrayAdapter<CharSequence>(getContext(), R.layout.auto_complete_text_list_item, getEntries()); inputView.setAdapter(adapter); inputView.setThreshold(1); inputView.setOnItemSelectedListener(this); layout.addView(inputView); return layout; }

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  • Pre Project Documentation

    - by DeanMc
    I have an issue that I feel many programmers can relate to... I have worked on many small scale projects. After my initial paper brain storm I tend to start coding. What I come up with is usually a rough working model of the actual application. I design in a disconnected fashion so I am talking about underlying code libraries, user interfaces are the last thing as the library usually dictates what is needed in the UI. As my projects get bigger I worry that so should my "spec" or design document. The above paragraph, from my investigations, is echoed all across the internet in one fashion or another. When a UI is concerned there is a bit more information but it is UI specific and does not relate to code libraries. What I am beginning to realise is that maybe code is code is code. It seems from my extensive research that there is no 1:1 mapping between a design document and the code. When I need to research a topic I dump information into OneNote and from there I prioritise features into versions and then into related chunks so that development runs in a fairly linear fashion, my tasks tend to look like so: Implement Binary File Reader Implement Binary File Writer Create Object to encapsulate Data for expression to the caller Now any programmer worth his salt is aware that between those three to do items could be a potential wall of code that could expand out to multiple files. I have tried to map the complete code process for each task but I simply don't think it can be done effectively. By the time one mangles pseudo code it is essentially code anyway so the time investment is negated. So my question is this: Am I right in assuming that the best documentation is the code itself. We are all in agreement that a high level overview is needed. How high should this be? Do you design to statement, class or concept level? What works for you?

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  • List of Big-O for PHP functions?

    - by Kendall Hopkins
    After using PHP for a while now, I've noticed that not all PHP built in functions as fast as expected. Consider the below two possible implementations of a function that finds if a number is prime using a cached array of primes. //very slow for large $prime_array $prime_array = array( 2, 3, 5, 7, 11, 13, .... 104729, ... ); $result_array = array(); foreach( $array_of_number => $number ) { $result_array[$number] = in_array( $number, $large_prime_array ); } //still decent performance for large $prime_array $prime_array => array( 2 => NULL, 3 => NULL, 5 => NULL, 7 => NULL, 11 => NULL, 13 => NULL, .... 104729 => NULL, ... ); foreach( $array_of_number => $number ) { $result_array[$number] = array_key_exists( $number, $large_prime_array ); } This is because in_array is implemented with a linear search O(n) which will linearly slow down as $prime_array grows. Where the array_key_exists function is implemented with a hash lookup O(1) which will not slow down unless the hash table gets extremely populated (in which case it's only O(logn)). So far I've had to discover the big-O's via trial and error, and occasionally looking at the source code. Now for the question... I was wondering if there was a list of the theoretical (or practical) big O times for all* the PHP built in functions. *or at least the interesting ones For example find it very hard to predict what the big O of functions listed because the possible implementation depends on unknown core data structures of PHP: array_merge, array_merge_recursive, array_reverse, array_intersect, array_combine, str_replace (with array inputs), etc.

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  • C# Finding 2 positions 1-dimArray

    - by Chris
    Hello, In a method i am calculating the longest row of elements. The 1-dim array is filled up with random values (0 or 1). The method looks up the longest row (being 0 or 1, whatever is the longest). Meaning in for example: 1110100 --> the longest row would be 3 (3 * 1) 0110000 --> the longest row would be 4 (4 * 0) My problem is i am trying to perform some type of linear search to show the position of the row in the array. The first example has the longest row of 3 elements (3 times 1). For 1110100 the position in the array would be 0 - 2 (index) For 0110000 the position in the array would be 3 - 6 (index) I have been trying with foreaches, for loops etc..but i cannot seem to get the proper indexes of both. Cannot seem to display both positions properly. For the first example the correct output wouldbe: The largest row of same elements of the array consists of 3 elements on the position 0 - 2. The longest row of elements gets of same elements get calculated as the following: public int BerekenDeelrij (int [] table) ( int count = 0; final int value = 0; int largest = 0; foreach (int value in table) ( if (value == last value) counter + +; else ( largest = Math.Max largest (largest, counter); final value = value count = 1; ) ) Math.Max return (largest, counter); ) Best Regards.

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  • Mobile detection - Meta tag and max-device-width vs. php user agent?

    - by nimmbl
    Which form of mobile detection should I use and why? <meta name="viewport" content="width=320,initial-scale=1,maximum-scale=1.0,user-scalable=no" /> <link media="only screen and (max-device-width: 480px) and (min-device-width: 320px)" href="css/mobile.css" type= "text/css" rel="stylesheet"> <link media="handheld, only screen and (max-device-width: 319px)" href="css/mobile_simple.css" type="text/css" rel="stylesheet" /> Or include('mobile_device_detect.php'); $mobile = mobile_device_detect(); And why on earth would this: <?php if(strpos($_SERVER['HTTP_USER_AGENT'], 'iPhone') !== false) { ?> <meta name="viewport" content="width=320,initial-scale=1,maximum-scale=1.0,user-scalable=no" /> <link media="screen" href="css/mobile.css" type= "text/css" rel="stylesheet"> <?php } else { ?> <link media="screen" href="css/mobile_simple.css" type= "text/css" rel="stylesheet"> <?php } ?> ignore this css? body { background: -webkit-gradient(linear, left top, left bottom, from(#555), to(#000)); }

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  • Out-of-memory algorithms for addressing large arrays

    - by reve_etrange
    I am trying to deal with a very large dataset. I have k = ~4200 matrices (varying sizes) which must be compared combinatorially, skipping non-unique and self comparisons. Each of k(k-1)/2 comparisons produces a matrix, which must be indexed against its parents (i.e. can find out where it came from). The convenient way to do this is to (triangularly) fill a k-by-k cell array with the result of each comparison. These are ~100 X ~100 matrices, on average. Using single precision floats, it works out to 400 GB overall. I need to 1) generate the cell array or pieces of it without trying to place the whole thing in memory and 2) access its elements (and their elements) in like fashion. My attempts have been inefficient due to reliance on MATLAB's eval() as well as save and clear occurring in loops. for i=1:k [~,m] = size(data{i}); cur_var = ['H' int2str(i)]; %# if i == 1; save('FileName'); end; %# If using a single MAT file and need to create it. eval([cur_var ' = cell(1,k-i);']); for j=i+1:k [~,n] = size(data{j}); eval([cur_var '{i,j} = zeros(m,n,''single'');']); eval([cur_var '{i,j} = compare(data{i},data{j});']); end save(cur_var,cur_var); %# Add '-append' when using a single MAT file. clear(cur_var); end The other thing I have done is to perform the split when mod((i+j-1)/2,max(factor(k(k-1)/2))) == 0. This divides the result into the largest number of same-size pieces, which seems logical. The indexing is a little more complicated, but not too bad because a linear index could be used. Does anyone know/see a better way?

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  • Efficient (basic) regular expression implementation for streaming data

    - by Brendan Dolan-Gavitt
    I'm looking for an implementation of regular expression matching that operates on a stream of data -- i.e., it has an API that allows a user to pass in one character at a time and report when a match is found on the stream of characters seen so far. Only very basic (classic) regular expressions are needed, so a DFA/NFA based implementation seems like it would be well-suited to the problem. Based on the fact that it's possible to do regular expression matching using a DFA/NFA in a single linear sweep, it seems like a streaming implementation should be possible. Requirements: The library should try to wait until the full string has been read before performing the match. The data I have really is streaming; there is no way to know how much data will arrive, it's not possible to seek forward or backward. Implementing specific stream matching for a couple special cases is not an option, as I don't know in advance what patterns a user might want to look for. For the curious, my use case is the following: I have a system which intercepts memory writes inside a full system emulator, and I would like to have a way to identify memory writes that match a regular expression (e.g., one could use this to find the point in the system where a URL is written to memory). I have found (links de-linkified because I don't have enough reputation): stackoverflow.com/questions/1962220/apply-a-regex-on-stream stackoverflow.com/questions/716927/applying-a-regular-expression-to-a-java-i-o-stream www.codeguru.com/csharp/csharp/cs_data/searching/article.php/c14689/Building-a-Regular-Expression-Stream-Search-with-the-NET-Framework.htm But all of these attempt to convert the stream to a string first and then use a stock regular expression library. Another thought I had was to modify the RE2 library, but according to the author it is architected around the assumption that the entire string is in memory at the same time. If nothing's available, then I can start down the unhappy path of reinventing this wheel to fit my own needs, but I'd really rather not if I can avoid it. Any help would be greatly appreciated!

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  • Why are changes to classes ignored after dom changes?

    - by Lg102
    I have a price grid that uses relative positioning to move a field around, beneath a box with: overflow: hidden;. In this is field, there are absolute-positioned boxes containing prices. When this box is hovered, the matching values above and left of the will change color. In order to achieve this, a class is toggled using jQuery. This initially works. However, after the grid is moved, the class change doesn't affect the block above the grid anymore. In the Chrome console, i can see the class being added, but it's css-styling isn't applied. No other styles for the element have changed. I am 100% sure there is no other style-rule influencing the element, it just stops responding to the change in class after the DOM has been altered. Can i 'refresh' the DOM somehow? Edit: I've tried to get the relevant code only: Adding the cell in the first place: $("#price_dates_cells").append("<div id='"+weekday[theBeginDate.getDay()]+"-"+theBeginDate.getDate()+"-"+(theBeginDate.getMonth()-1)+"' class='datecell' style='left: "+( Math.floor( difference / ( 3600 * 24 * 1000) ) * ( cellwidth ) )+"px'>"+weekday[theBeginDate.getDay()]+"<br>"+theBeginDate.getDate()+" "+yearmonth[theBeginDate.getMonth()]+"</div>"); Toggle the class: var str_element = "#"+weekday[Bdate.getDay()]+"-"+Bdate.getDate()+"-"+(Bdate.getMonth()-1); $(str_element).toggleClass("red"); and the movement that seems to cause the problem: $('#price_grid').animate({"top": (( ( horizontalMovement ) * cellheight)) }, 'fast', 'linear');

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  • breadth-first traversal of directory tree is not lazy

    - by user855443
    I try to traverse the diretory tree. A naive depth-first traversal seems not to produce the data in a lazy fashion and runs out of memory. I next tried a breadth first approach, which shows the same problem - it uses all the memory available and then crashes. the code i have is: getFilePathBreadtFirst :: FilePath -> IO [FilePath] getFilePathBreadtFirst fp = do fileinfo <- getInfo fp res :: [FilePath] <- if isReadableDirectory fileinfo then do children <- getChildren fp lower <- mapM getFilePathBreadtFirst children return (children ++ concat lower) return (children ++ concat () else return [fp] -- should only return the files? return res getChildren :: FilePath -> IO [FilePath] getChildren path = do names <- getUsefulContents path let namesfull = map (path </>) names return namesfull testBF fn = do -- crashes for /home/frank, does not go to swap fps <- getFilePathBreadtFirst fn putStrLn $ unlines fps I think all the code is either linear or tail recursive, and I would expect that the listing of filenames starts immediately, but in fact it does not. Where is the error in my code and my thinking? where have I lost lazy evaluation?

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  • Convert SVG to PDF

    - by Adrian Smith
    How would one go about converting a SVG file to a PDF programatically? (I need to alter the SVG in certain respects before generating the PDF so simply pre-converting it using a tool won't be sufficient.) Ideally using Java but Perl or PHP would be fine too. Obviously I am basically considering Apache FOP and Batik with Java. However no matter how long I search I cannot find a simple introduction on how to do it. Things like SVGConverter have descriptions like "Defines the interface for classes that are able to convert part or all of a GraphicContext", but I don't really know what that means. I have this feeling there must be an API to do this quite simply, provided by FOP or Batik, but I'm just not able to find it at the moment (or perhaps it really doesn't exist.) In terms of the supported SVG features I need, the file has some paths which are filled with some linear gradients. Ideally if I could pass the SVG in as a DOM Document that would be ideal; then I would load my template SVG file, change it as specified by the user, and then generate the PDF.

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  • R Tree 50,000 foot overview?

    - by roufamatic
    I'm working on a school project that involves taking a lat/long point and finding the top five closest points in a known list of places. The list is to be stored in memory, with the caveat that we must choose an "appropriate data structure" -- that is, we cannot simply store all the places in an array and compare distances one-by-one in a linear fashion. The teacher suggested grouping the place data by US State to prevent calculating the distance for places that are obviously too far away. I think I can do better. From my research online it seems like an R-Tree or one of its variants might be a neat solution. Unfortunately, that sentence is as far as I've gotten with understanding the actual technique, as the literature is simply too dense for my non-academic head. Can somebody give me a really high overview of what the process is for populating an R-Tree with lat/long data, and then traversing the tree to find those 5 nearest neighbors of a given point? Additionally the project is in C, and I don't have to reinvent the wheel on this, so if you've used an existing open source C implementation of an R Tree I'd be interested in your experiences.

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  • Algorithm to determine if array contains n...n+m?

    - by Kyle Cronin
    I saw this question on Reddit, and there were no positive solutions presented, and I thought it would be a perfect question to ask here. This was in a thread about interview questions: Write a method that takes an int array of size m, and returns (True/False) if the array consists of the numbers n...n+m-1, all numbers in that range and only numbers in that range. The array is not guaranteed to be sorted. (For instance, {2,3,4} would return true. {1,3,1} would return false, {1,2,4} would return false. The problem I had with this one is that my interviewer kept asking me to optimize (faster O(n), less memory, etc), to the point where he claimed you could do it in one pass of the array using a constant amount of memory. Never figured that one out. Along with your solutions please indicate if they assume that the array contains unique items. Also indicate if your solution assumes the sequence starts at 1. (I've modified the question slightly to allow cases where it goes 2, 3, 4...) edit: I am now of the opinion that there does not exist a linear in time and constant in space algorithm that handles duplicates. Can anyone verify this? The duplicate problem boils down to testing to see if the array contains duplicates in O(n) time, O(1) space. If this can be done you can simply test first and if there are no duplicates run the algorithms posted. So can you test for dupes in O(n) time O(1) space?

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  • Low Throughput on Windows Named Pipe Over WAN

    - by MichaelB76
    I'm having problems with low performance using a Windows named pipe. The throughput drops off rapidly as the network latency increases. There is a roughly linear relationship between messages sent per second and round trip time. It seems that the client must ack each message before the server will send the next one. This leads to very poor performance, I can only send 5 (~100 byte) messages per second over a link with an RTT of 200 ms. The pipe is asynchronous, using multiple overlapped write operations (and multiple overlapped reads at the client end), but this is not improving throughput. Is it possible to send messages in parallel over a named pipe? The pipe is created using PIPE_TYPE_MESSAGE, would PIPE_READMODE_BYTE work better? Is there any other way I can improve performance? This is a deployed solution, so I can't simply replace the pipe with a socket connection (I've read that Windows named pipe aren't recommended for use over a WAN, and I'm wondering if this is why). I'd be grateful for any help with this matter.

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  • Hashing Function for Map C++

    - by Josh
    I am trying to determine a hash function which takes an input (i, k) and determines a unique solution. The possible inputs for (i, k) range from 0 to 100. Consider each (i, k) as a position of a node in a trinomial tree. Ex: (0, 0) can diverge to (1, 1) (1, 0) (1, -1). (1, 1) can diverge to (2, 2) (2, 1) (2, 0). Sample given here: http://www.google.com/imgres?imgurl=http://sfb649.wiwi.hu-berlin.de/fedc_homepage/xplore/tutorials/stfhtmlimg1156.gif&imgrefurl=http://sfb649.wiwi.hu-berlin.de/fedc_homepage/xplore/tutorials/stfhtmlnode41.html&h=413&w=416&sz=4&tbnid=OegDZu-yeVitZM:&tbnh=90&tbnw=91&zoom=1&usg=__9uQWDNYNLV14YioWWbrqPgfa3DQ=&docid=2hhitNyRWjI_DM&hl=en&sa=X&ei=xAfFUIbyG8nzyAHv2YDICg&ved=0CDsQ9QEwAQ I am using a map map <double, double> hash_table I need a key value to be determined from pairs (i, k) to hash to to value for that (i, k) So far I was only able to come up with linear functions such as: double Hash_function(int i, int k) { //double val = pow(i, k) + i; //return (val % 4294967296); return (i*3.1415 + k*i*9.12341); } However, I cannot determine a unique key with a certain (i, k). What kind of functions can I use to help me do so?

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  • C++ map performance - Linux (30 sec) vs Windows (30 mins) !!!

    - by sonofdelphi
    I need to process a list of files. The processing action should not be repeated for the same file. The code I am using for this is - using namespace std; vector<File*> gInputFileList; //Can contain duplicates, File has member sFilename map<string, File*> gProcessedFileList; //Using map to avoid linear search costs void processFile(File* pFile) { File* pProcessedFile = gProcessedFileList[pFile->sFilename]; if(pProcessedFile != NULL) return; //Already processed foo(pFile); //foo() is the action to do for each file gProcessedFileList[pFile->sFilename] = pFile; } void main() { size_t n= gInputFileList.size(); //Using array syntax (iterator syntax also gives identical performance) for(size_t i=0; i<n; i++){ processFile(gInputFileList[i]); } } The code works correctly, but... My problem is that when the input size is 1000, it takes 30 minutes - HALF AN HOUR - on Windows/Visual Studio 2008 Express (both Debug and Release builds). For the same input, it takes only 40 seconds to run on Linux/gcc! What could be the problem? The action foo() takes only a very short time to execute, when used separately. Should I be using something like vector::reserve for the map?

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  • Dynamically adding custom view to RemoteViews

    - by Naidu
    Could any help me to do this?My code is like: public CustomClass extends View { //uses ondraw() to do something } For displaying my custom view on HomeScreen i created a class to extend Broadcast Receiver public class customAppWidgetProvider extends BroadcastReceiver { public void onReceive(Context context, Intent intent) { String action = intent.getAction(); if (AppWidgetManager.ACTION_APPWIDGET_UPDATE.equals(action)) { RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.main); //Here i want to create my custom view class object and i want to add this view to linear layout in main.xml CustomClass object = new CustomClass(context) ; LinearLayout layout = new LinearLayout(context) ; layout.setLayoutParameters(new LayoutParameters(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT)); layout.addView(object); views.addview(R.id.linearlayout, (ViewGroup) layout) ; views.setOnClickPendingIntent(R.id.analog_appwidget, PendingIntent.getActivity(context, 0, new Intent(context, AlarmClock.class), PendingIntent.FLAG_CANCEL_CURRENT)); int[] appWidgetIds = intent.getIntArrayExtra( AppWidgetManager.EXTRA_APPWIDGET_IDS); AppWidgetManager gm = AppWidgetManager.getInstance(context); gm.updateAppWidget(appWidgetIds, views); } } } But adding viewgroup to RemoteView reference is not working... above main.xml contains only LinearLayout.I want to add custom view object to it.But after running this not showing anything on screen.. please help me to do this.Thanks in Advance.

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  • Dynamically changing layout

    - by LTMOD
    I have a 2 x 2 grid of buttons. Each row of 2 is wrapped in a horizontal linear layout. <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="100dip"> <Button android:layout_weight=".5" android:id="@+id/btn1" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_gravity="center_vertical|center_horizontal" android:padding="5dip" android:layout_margin="2dip"> </Button> <Button android:layout_weight=".5" android:id="@+id/btn2" android:layout_width="fill_parent" android:layout_height="fill_parent" android:padding="5dip" android:layout_margin="2dip"> </Button> At times I want to show all 4 buttons, and other times, I show the top 2 only, and sometimes, I need to show 2 on top, and one on the bottom. I would like to center the bottom one, but can't seem to accomplish this. In my code, I call btn4.setVisibility(8); //8 = GONE, which makes my 4th button disappear, but then btn3 ends up filling the entire layout. What I would like it to do instead is center itself within the layout at its correct width / height. I'm a bit new to this, so any help is greatly appreciated. Thanks in advance!

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  • WD1000FYPS harddrive is marked 0 mb in 3ware (and no SMART)

    - by osgx
    After reboot my SATA 1TB WD1000FYPS (previously is was "Drive error") is marked 0 mb in 3ware web gui. Complete message: Available Drives (Controller ID 0) Port 1 WDC WD1000FYPS-01ZKB0 0.00 MB NOT SUPPORTED [Remove Drive] SMART gives me only Device Model and ATA protocol version 1 (not 7-8 as it must be for SATA) What does it mean? Just before reboot, when is was marked only with "Device Error", smart was: Device Model: WDC WD1000FYPS-01ZKB0 Serial Number: WD-WCASJ1130*** Firmware Version: 02.01B01 User Capacity: 1,000,204,886,016 bytes Device is: Not in smartctl database [for details use: -P showall] ATA Version is: 8 ATA Standard is: Exact ATA specification draft version not indicated Local Time is: Sun Mar 7 18:47:35 2010 MSK SMART support is: Available - device has SMART capability. SMART support is: Enabled SMART overall-health self-assessment test result: PASSED SMART Attributes Data Structure revision number: 16 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x000f 200 200 051 Pre-fail Always - 0 3 Spin_Up_Time 0x0003 188 186 021 Pre-fail Always - 7591 4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 229 5 Reallocated_Sector_Ct 0x0033 199 199 140 Pre-fail Always - 3 7 Seek_Error_Rate 0x000e 193 193 000 Old_age Always - 125 9 Power_On_Hours 0x0032 078 078 000 Old_age Always - 16615 10 Spin_Retry_Count 0x0012 100 100 000 Old_age Always - 0 11 Calibration_Retry_Count 0x0012 100 253 000 Old_age Always - 0 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 77 192 Power-Off_Retract_Count 0x0032 198 198 000 Old_age Always - 1564 193 Load_Cycle_Count 0x0032 146 146 000 Old_age Always - 164824 194 Temperature_Celsius 0x0022 117 100 000 Old_age Always - 35 196 Reallocated_Event_Count 0x0032 199 199 000 Old_age Always - 1 197 Current_Pending_Sector 0x0012 200 200 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0010 200 200 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x003e 200 200 000 Old_age Always - 0 200 Multi_Zone_Error_Rate 0x0008 200 200 000 Old_age Offline - 0 What can be wrong with he? Can it be restored? PS new smart is === START OF INFORMATION SECTION === Device Model: WDC WD1000FYPS-01ZKB0 Serial Number: [No Information Found] Firmware Version: [No Information Found] Device is: Not in smartctl database [for details use: -P showall] ATA Version is: 1 ATA Standard is: Exact ATA specification draft version not indicated Local Time is: Mon Mar 8 00:29:44 2010 MSK SMART is only available in ATA Version 3 Revision 3 or greater. We will try to proceed in spite of this. SMART support is: Ambiguous - ATA IDENTIFY DEVICE words 82-83 don't show if SMART supported. Checking for SMART support by trying SMART ENABLE command. Command failed, ata.status=(0x00), ata.command=(0x51), ata.flags=(0x01) Error SMART Enable failed: Input/output error SMART ENABLE failed - this establishes that this device lacks SMART functionality. A mandatory SMART command failed: exiting. To continue, add one or more '-T permissive' options. PPS There was a rapid grow of " 192 Power-Off_Retract_Count " before dying. The hard was used in raid, with several hards from the same fabric packaging box (close id's). The hard drives were placed identically. Rapid means almost linear grow from 300 to 1700 in 6-7 hours. Maximal temperature was 41C. (thanks to munin's smart monitoring)

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  • where on disk is space allocated for new files inside LVM lv with ext4 file system?

    - by Jost
    I run a multi-disk server with LVM2. Several large disks serve as LVM2 physical volumes for one volume group, containing one logical volume formatted with ext4. Nothing fancy, just your standard linear setup. Recently an additional, very small disk was added as physical volume to that volume group and I expanded both the logical volume, and the ext4 file system therein onto that disk. This lv is used to store incremental backups using rsync and is only about 30% full, there have rarely been any files deleted from it, only incremental writes. Now this new HDD I added to the pre-existing volume group has unexpectedly died on me, and the volume group won't come up because it is missing one physical volume. As fate will have it, this WAS the "in an event of catastrophic failure on the primary server"-backup, the event happened, the boss is not happy, so this kinda has to work... According to this (Part 3): http://www.novell.com/coolsolutions/appnote/19386.html it is possible to trick LVM into starting anyway by creating a new pv with identical metadata to the failed disk, which will make the volume accessible, but of course leave giant holes in the file system. I have'n tried it yet, because it involves repairing (writing to) the file system which eliminates the possibility of trying other things if it fails. Now my question is: How does this setup actually allocate disk space for new data? Is it allocated linearly from beginning to end of PVs, in the order they were added to the vg? Is it striped somehow in order to increase performance/balance load? since this defective disk was added only later to an existing lvm2 vg and lv, containing a half-empty ext4, what are the chances that there was never any data written to the defective disk? In other words: what are the chances of recovering all my data, even without the defective disk, by just starting the volume group as-is? Am I about to go spend $1500 on having 250GB of empty space recovered when I send the defective disk in for repair? Is there a way to check without mounting the file system and opening the files, hoping they contain something other than zeros? (comparing addresses of used data blocks inside ext4 to address ranges that were on the missing pv, something like that, preferably easy to automate) I know bitwise-copying the entire lv into an image file before trying to repair the ext4 would probably be a good idea, but since this lv is very large and I just suffered major file system failure on several systems it is probably a luxury I don't have... Any suggestions?

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