Search Results

Search found 11587 results on 464 pages for 'pseudo random numbers'.

Page 306/464 | < Previous Page | 302 303 304 305 306 307 308 309 310 311 312 313  | Next Page >

• Optimal Sharing of heavy computation job using Snow and/or multicore

  - by James

  Hi, I have the following problem. First my environment, I have two 24-CPU servers to work with and one big job (resampling a large dataset) to share among them. I've setup multicore and (a socket) Snow cluster on each. As a high-level interface I'm using foreach. What is the optimal sharing of the job? Should I setup a Snow cluster using CPUs from both machines and split the job that way (i.e. use doSNOW for the foreach loop). Or should I use the two servers separately and use multicore on each server (i.e. split the job in two chunks, run them on each server and then stich it back together). Basically what is an easy way to: 1. Keep communication between servers down (since this is probably the slowest bit). 2. Ensure that the random numbers generated in the servers are not highly correlated.

  Read the article

• Mutual Information / Entropy Calculation Help

  - by Fillip

  Hi, Hoping someone can give me some pointers with this entropy problem. Say X is chosen randomly from the uniform integer distribution 0-32 (inclusive). I calculate the entropy, H(X) = 32 bits, as each Xi has equal probability of occurring. Now, say the following pseudocode executes. int r = rand(0,1); // a random integer 0 or 1 r = r * 33 + X; How would I work out the mutual information between the two variables r and X? Mutual Information is defined as I(X; Y) = H(X) - H(X|Y) but I don't really understand how to apply the conditional entropy H(X|Y) to this problem. Thanks

  Read the article

• AdvancedDataGrid LockedRowCount not working

  - by online19

  I am trying to lock the 1st row in my ADG. This 1st row is the SummaryRow. When I set the lockedRowCount property to 1, it still does not freeze the 1st row. I have tried with different numbers, but it is still not working. In fact, when I try to trace the value for lockedRowCount, it traces it as 0. Can anyone provide suggestion on how to do this with the lockedRowCount property or if you can provide me with another workaround, that'll be great. Thanks :)

  Read the article

• Centralizing a floating element :(

  - by 2x2p1p

  Hi guys :| My "div" element have a relative width, it isn't absolute so I can't use exact numbers to centralize. A nice solution is to use "display: inline-block": body { text-align: center; } #myDiv { border: 1px solid black; display: inline-block; padding: 50px; } But this element NEEDS to float, I tried this: #myDiv { border: 1px solid black; display: inline-block; float: left; padding: 50px; } And this: #myDiv { border: 1px solid black; display: inline-block; padding: 50px; position: absolute; } Without any success, can somebody help me ? Thanks

  Read the article

• How do I modify this download function in Python?

  - by TIMEX

  Right now, it's iffy. Gzip, images, sometimes it doesn't work. How do I modify this download function so that it can work with anything? (Regardless of gzip or any header?) How do I automatically "Detect" if it's gzip? I don't want to always pass True/False, like I do right now. def download(source_url, g = False, correct_url = True): try: socket.setdefaulttimeout(10) agents = ['Mozilla/4.0 (compatible; MSIE 5.5; Windows NT 5.0)','Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1)','Microsoft Internet Explorer/4.0b1 (Windows 95)','Opera/8.00 (Windows NT 5.1; U; en)'] ree = urllib2.Request(source_url) ree.add_header('User-Agent',random.choice(agents)) ree.add_header('Accept-encoding', 'gzip') opener = urllib2.build_opener() h = opener.open(ree).read() if g: compressedstream = StringIO(h) gzipper = gzip.GzipFile(fileobj=compressedstream) data = gzipper.read() return data else: return h except Exception, e: return ""

  Read the article

• Avoiding a fork()/SIGCHLD race condition

  - by larry

  Please consider the following fork()/SIGCHLD pseudo-code. // main program excerpt for (;;) { if ( is_time_to_make_babies ) { pid = fork(); if (pid == -1) { /* fail */ } else if (pid == 0) { /* child stuff */ print "child started" exit } else { /* parent stuff */ print "parent forked new child ", pid children.add(pid); } } } // SIGCHLD handler sigchld_handler(signo) { while ( (pid = wait(status, WNOHANG)) > 0 ) { print "parent caught SIGCHLD from ", pid children.remove(pid); } } In the above example there's a race-condition. It's possible for "/* child stuff */" to finish before "/* parent stuff */" starts which can result in a child's pid being added to the list of children after it's exited, and never being removed. When the time comes for the app to close down, the parent will wait endlessly for the already-finished child to finish. One solution I can think of to counter this is to have two lists: started_children and finished_children. I'd add to started_children in the same place I'm adding to children now. But in the signal handler, instead of removing from children I'd add to finished_children. When the app closes down, the parent can simply wait until the difference between started_children and finished_children is zero. Another possible solution I can think of is using shared-memory, e.g. share the parent's list of children and let the children .add and .remove themselves? But I don't know too much about this. EDIT: Another possible solution, which was the first thing that came to mind, is to simply add a sleep(1) at the start of /* child stuff */ but that smells funny to me, which is why I left it out. I'm also not even sure it's a 100% fix. So, how would you correct this race-condition? And if there's a well-established recommended pattern for this, please let me know! Thanks.

  Read the article

• Why might different computers calculate different arithmetic results in VB.NET?

  - by Eyal

  I have some software written in VB.NET that performs a lot of calculations, mostly extracting jpegs to bitmaps and computing calculations on the pixels like convolutions and matrix multiplication. Different computers are giving me different results despite having identical inputs. What might be the reason? Edit: I can't provide the algorithm because it's proprietary but I can provide all the relevant operations: ULong \ ULong (Turuncating division) Bitmap.Load("filename.bmp') (Load a bitmap into memory) Bitmap.GetPixel(Integer, Integer) (Get a pixel's brightness) Double + Double Double * Double Math.Sqrt(Double) Math.PI Math.Cos(Double) ULong - ULong ULong * ULong ULong << ULong List.OrderBy(Of Double)(Func) Hmm... Is it possible that OrderBy is using a non-stable QuickSort and that QuickSort is using a random pivot? Edit: Just tested, nope. The sort is stable.

  Read the article

• How do you solve this Haskell problem using a fold map and take?

  - by Linda Cohen

  Define a function replicate which given a list of numbers returns a list with each number duplicated its value. Use a fold, map, and take .. replicate [5,1,3,2,8,1,2] output: [5,5,5,5,5,1,3,3,3,2,2,8,8,8,8,8,8,8,8,1,2,2] I've figure this out using List comprehension and recursion: replicate2 [] = [] replicate2 (n:nn) = take n(repeat n) ++ replicate2 nn but how would you use fold and map to do this? so far I have: replicate n = map (foldl1 (take n(repeat n)) n) n which is obviously wrong, but I think I am close.. so any help would be nice, THANKS!

  Read the article

• Subset generation by rules

  - by Sazug

  Let's say that we have a 5000 users in database. User row has sex column, place where he/she was born column and status (married or not married) column. How to generate a random subset (let's say 100 users) that would satisfy these conditions: 40% should be males and 60% - females 50% should be born in USA, 20% born in UK, 20% born in Canada, 10% in Australia 70% should be married and 30% not. These conditions are independent, that is we cannot do like this: (0.4 * 0.5 * 0.7) * 100 = 14 users that are males, born in USA and married (0.4 * 0.5 * 0.3) * 100 = 6 users that are males, born in USA and not married. Is there an algorithm to this generation?

  Read the article

• Formatting a query to enumerate through 2 different datatables

  - by boiler1974

  I have 2 datatables sendTable and recvTable They both have identical column names and numbers of columns "NODE" "DSP Name" "BUS" "IDENT" "STATION" "REF1" "REF2" "REF3" "REF4" "REF5" "REF6" "REF7" "REF8" I need to compare these 2 tables and separate out the mismatches I only need to check Columns 3-11 and Ignore col 1 and 2 I tried at first removing the 2 columns and then loop thru row by row and return matches and mismatches but the problem with this approach is that I no longer have the "NODE" and "DSP Name" associated with the row when I finalize my results So I need help with a query Here is my attempt var samerecordQuery = from r1 in sendTable.AsEnumerable() where r1.Field<int>("BUS").Equals(from r2 in recvTable.AsEnumerable() where r2.Field<int>("BUS")) this obviously doesn't work so how do I format the query to say from r1 cols[3-11] equals r2 cols [3-11] and once I have this I can use the except to pull out the mismatches

  Read the article

• search paths where one native library depends on another

  - by carneades

  I'm using JNA and Java but I think this question affects any native-to-nonnative bridge. I have a Java application which relies on lib1.dylib, and lib1.dylib relies on lib2.dylib. I want to put everything inside of my .app file on Mac. I can easily put lib1.dylib inside and set java.classpath (or NativeLibrary.addSearchPath()) to tell the JVM where to find lib1.dylib. The trouble is, I don't know how to communicate that lib1.dylib's dependencies are also in the location I provided. The result is that lib1 is loaded fine, but then lib2 can't be found since it's not in the operating system's library path. Anyone know how I can overcome this problem? I imagine it must come up plenty in big projects with large numbers of shared libraries.

  Read the article

• How do I use Some/None Options in this F# example?

  - by Phobis

  I am new to F# and I have this code: if s.Contains("-") then let x,y = match s.Split [|'-'|] with | [|a;b|] -> int a, int b | _ -> 0,0 Notice that we validate that there is a '-' in the string before we split the string, so the match is really unnecessary. Can I rewrite this with Options? I changed this code, it was originally this (but I was getting a warning): if s.Contains("-") then let [|a;b|] = s.Split [|'-'|] let x,y = int a, int b NOTE: I am splitting a range of numbers (range is expressed in a string) and then creating the integer values that represent the range's minimum and maximum.

  Read the article

• How to replace values in multi-valued ESE column?

  - by Soonts

  I have a multi-valued short ASCII text column in one of the tables in my ESE database, that holds the person's phone numbers. I have the new set of values, and I'd like to wipe the old values completely, and only use the new values. The JET_bitSetRevertToDefaultValue bit doesn't seem to work. While the MSDN documentation says "It causes the column to return the default column value on subsequent retrieve column operations. All existing column values are removed.", I found that it does nothing (no return value is returned). Or, is there an easy way to find out how many values does the column contain (this could be zero, e.g. when I'm doing an insertion, not update)? If it was, I could just run a loop from 'nValues' to 1, erasing the value by setting it to the null while providing the itagSequence value, to achieve what I want. I'm programming C#, and using the latest version of ManagedEsent library. Thanks in advance!

  Read the article

• JavaScript data grid for millions of rows

  - by Rudiger

  I need to present millions of rows of data to users in a grid using JavaScript. I don't want the user thinking about viewing finite pieces of data; it should appear that all of the data is available. Rather than downloading all the data at once, small chunks are downloaded as the user comes to them (by scrolling, keying in row numbers, searching). The rows will not be edited through this front end, so read-only answers are acceptable. What JavaScript data grids are best for this kind of seamless paging?

  Read the article

• strtod() and sprintf() inconsistency under GCC and MSVC

  - by Dmitry Sapelnikov

  I'm working on a cross-platform app for Windows and Mac OS X, and I have a problem with two standard C library functions: strtod() - string-to-double conversion sprintf() - when used for outputting double-precision floating point numbers) Their GCC and MSVC versions return different results. I'm looking for a well-tested cross-platform open-source implementation of those functions, or just for a pair of functions that would correctly and consistently convert double to string and back. I've already tried the clib GCC implementation, but the code is too long and too dependent on other source files, so I expect the adaptation to be difficult. What implementations of string-to-double and double-to-string functions would you recommend?

  Read the article

• How to make tag group with including predefined attributes, to wrap other things quickly?

  - by jitendra

  for example. if i want to quickly wrap anything by this in once. in dreamweaver or in any other free software where i can do this. I want to select this <p>anything can be here - content, other html tag etc.</p> and in one shot want to wrap inside 2 divs with predefined classes <div class="one"> <div class="two"> <p>anything can be here - content, other html tag etc.</p> </div> </div> I have work with large amount of code and need to wrap random things in Divs with defined attributes.

  Read the article

• Code/Approach Golf: Find row in text file with too many columns

  - by awshepard

  Given a text file that is supposed to contain 10 tab-delimited columns (i.e. 9 tabs), I'd like to find all rows that have more than 10 columns (more than 9 tabs). Each row ends with CR-LF. Assume nothing about the data, field widths, etc, other than the above. Comments regarding approach, and/or working code would be extremely appreciated. Bonus for printing line numbers of offending lines as well. Thanks in advance!

  Read the article

• How to check a radio button based upon the enum value

  - by user281180

  I have an enum. Based upon the value brought by model, I have to check radio button. How can I do that? <%=Html.RadioButton("Role", Role.Viewer)%><%= .Role.Viewer%> <%=Html.RadioButton("Role",.Role.Reporter)%><%= Role.Reporter%> <%=Html.RadioButton("Role",Role.User)%><%= Role.User%> My enum would be having the numbers 1 to 3 for e.g. How can I check the Role.Viewer if enum value selected is 1?

  Read the article

• How to find scrollable elements in DOM using XPath?

  - by ak.

  Basically I need to find all elements on the page that have a scrollbar (vertical or horizontal) How to tell if an element has a scrollbar and can actually be scrolled? I found this code snippet on jsperf. Is it possible to capture the logic behind the code into and XPath expression? Or are there any other ways to check for scrollbars? Added: Just to explain what I'm trying to do: I'm developing extension for Firefox. Basically it introduces Vim-style mouseless shortcuts (I know there is Vimperator and Pentadactyl...). One of the features I'd like to implement is to allow the use to select the container that's scrolled with j/k keys. That's why I need to discover all scrollable elements on any given random page.

  Read the article

• Filtering data in an array.

  - by user276424

  Hi all, I have an array that has 30 date objects. The date objects are indexed in the array from the minimum date value to the maximum date value. What I would like to do is retrieve only 7 dates from the array. Out of the 7, the first one should be the minDate and the last should be the maxDate, with 5 dates in the middle. The 7 numbers should increment evenly from the minDate to the maxDate. How would I accomplish this? Hope I was clear. Thanks, Tonih

  Read the article

• Cocoa window position anomaly

  - by Marius

  Hello everyone, I have a weird problem with positioning a window on screen. I want to center the window on the screen, but i don't know how to do that. Here's what i've got. The window is created from nib by the main controller: IdentFormController *ftf = [[IdentFormController alloc] initWithWindowNibName:@"IdentForm"]; [[ftf window] makeKeyAndOrderFront:self]; Now the IdentFormController has awakeFromNib() method in which it tries to position the window. For the sake of simplicity i've just tried to do setFrameOrigin(NSMakePoint(0, 0)). What happens is as follows: The first time i create this window, everything works as expected. But if i create it again after releasing the previous, it starts appearing at random positions. Why does it do that?

  Read the article

• Python and hebrew encoding/decoding error

  - by user340495

  Hey, I have sqlite database which I would like to insert values in Hebrew to I am keep getting the following error : UnicodeDecodeError: 'ascii' codec can't decode byte 0xd7 in position 0: ordinal not in range(128) my code is as following : runsql(u'INSERT into personal values(%(ID)d,%(name)s)' % {'ID':1,'name':fabricate_hebrew_name()}) def fabricate_hebrew_name(): hebrew_names = [u'????',u'???',u'???',u'???',u'????',u'???',u'????',u'???',u'????',u'?????',u'????',u'???',u'????'] return random.sample(names,1)[0].encode('utf-8') note: runsql executing the query on the sqlite database fabricate_hebrew_name() should return a string which could be used in my SQL query. any help is much appreciated.

  Read the article

• VS2005 project has dependency that is not built

  - by Eyal

  I have VS2005 solution that contains many projects and dependencies (some C++, some C#) - in the past it compiled successfully. when I rebuild all the solution it fails on a project claiming dll is missing (dll that was needed to built before according to dependency). the thing is that from time to time it fails on random project (not all the time the same project). I'm not sure it is meaningful but I see in output console Deleting intermediate and output files for project doesn't VS2005 go according to "Project Build Order" and ReBuild every project starting with its dependencies?

  Read the article

• What's the best way to offer javascript embed that won't slow a page down?

  - by Shpigford

  I have a chunk of javascript that users can copy and paste to put on their sites. I'm currently using the following code (ala WEDJE) that allows the rest of the page to load even if my script is slow or not responding. <script type="text/javascript"> var number = "987654321"; var key = "123abc"; (function(){ document.write('<div id="ttp"></div>'); s=document.createElement('script'); s.type="text/javascript"; s.src="http://example.com/javascripts/embed.js?" + Math.random(); setTimeout("document.getElementById('ttp').appendChild(s);",1); })() </script> But that method is a few years old and so I wasn't sure if there was a more efficient way of doing the same thing that others have come up with.

  Read the article

• How to format a string as a telephone number in C#

  - by Brian G

  I have a string "1112224444' it is a telephone number. I want to format as 111-222-4444 before I store it in a file. It is on a datarecord and I would prefer to be able to do this without assigning a new variable. I was thinking: String.Format("{0:###-###-####}", i["MyPhone"].ToString() ); but that does not seem to do the trick. ** UPDATE ** Ok. I went with this solution Convert.ToInt64(i["Customer Phone"]).ToString("###-###-#### ####") Now its gets messed up when the extension is less than 4 digits. It will fill in the numbers from the right. so 1112224444 333 becomes 11-221-244 3334 Any ideas?

  Read the article

< Previous Page | 302 303 304 305 306 307 308 309 310 311 312 313  | Next Page >