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  • Very simple python functions takes spends long time in function and not subfunctions

    - by John Salvatier
    I have spent many hours trying to figure what is going on here. The function 'grad_logp' in the code below is called many times in my program, and cProfile and runsnakerun the visualize the results reveals that the function grad_logp spends about .00004s 'locally' every call not in any functions it calls and the function 'n' spends about .00006s locally every call. Together these two times make up about 30% of program time that I care about. It doesn't seem like this is function overhead as other python functions spend far less time 'locally' and merging 'grad_logp' and 'n' does not make my program faster, but the operations that these two functions do seem rather trivial. Does anyone have any suggestions on what might be happening? Have I done something obviously inefficient? Am I misunderstanding how cProfile works? def grad_logp(self, variable, calculation_set ): p = params(self.p,self.parents) return self.n(variable, self.p) def n (self, variable, p ): gradient = self.gg(variable, p) return np.reshape(gradient, np.shape(variable.value)) def gg(self, variable, p): if variable is self: gradient = self._grad_logps['x']( x = self.value, **p) else: gradient = __builtin__.sum([self._pgradient(variable, parameter, value, p) for parameter, value in self.parents.iteritems()]) return gradient

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  • Is it getting to be time for C# to support compile-time macros?

    - by Robert Rossney
    Thus far, Microsoft's C# team has resisted adding formal compile-time macro capabilities to the language. There are aspects of programming with WPF that seem (to me, at least) to be creating some compelling use cases for macros. Dependency properties, for instance. It would be so nice to just be able to do something like this: [DependencyProperty] public string Foo { get; set; } and have the body of the Foo property and the static FooProperty property be generated automatically at compile time. Or, for another example an attribute like this: [NotifyPropertyChanged] public string Foo { get; set; } that would make the currently-nonexistent preprocessor produce this: private string _Foo; public string Foo { get { return _Foo; } set { _Foo = value; OnPropertyChanged("Foo"); } } You can implement change notification with PostSharp, and really, maybe PostSharp is a better answer to the question. I really don't know. Assuming that you've thought about this more than I have, which if you've thought about it at all you probably have, what do you think? (This is clearly a community wiki question and I've marked it accordingly.)

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  • Tricky SQL query - need to get time frames

    - by Andrew
    I am stumbled upon a problem, when I need a query which will produce a list of speeding time frames. Here is the data example [idgps_unit_location] [dt] [idgps_unit] [lat] [long] [speed_kmh] 26 10/18/2012 18:53 2 47 56 30 27 10/18/2012 18:53 2 49 58 31 28 10/18/2012 18:53 2 28 37 15 29 10/18/2012 18:54 2 56 65 33 30 10/18/2012 18:54 2 152 161 73 31 10/18/2012 18:55 2 134 143 64 32 10/18/2012 18:56 2 22 31 12 36 10/18/2012 18:59 2 98 107 47 37 10/18/2012 18:59 2 122 131 58 38 10/18/2012 18:59 2 91 100 44 39 10/18/2012 19:00 2 190 199 98 40 10/18/2012 19:01 2 194 203 101 41 10/18/2012 19:02 2 182 191 91 42 10/18/2012 19:03 2 162 171 78 43 10/18/2012 19:03 2 174 183 83 44 10/18/2012 19:04 2 170 179 81 45 10/18/2012 19:05 2 189 198 97 46 10/18/2012 19:06 2 20 29 10 47 10/18/2012 19:07 2 158 167 76 48 10/18/2012 19:08 2 135 144 64 49 10/18/2012 19:08 2 166 175 79 50 10/18/2012 19:09 2 9 18 5 51 10/18/2012 19:09 2 101 110 48 52 10/18/2012 19:09 2 10 19 7 53 10/18/2012 19:10 2 32 41 20 54 10/18/2012 19:10 1 54 63 85 55 10/19/2012 19:11 2 55 64 50 I need a query that would convert this table into the following report that shows frames of time when speed was 80: [idgps_unit] [dt_start] [lat_start] [long_start] [speed_start] [dt_end] [lat_end] [long_end] [speed_end] [speed_average] 2 10/18/2012 19:00 190 199 98 10/18/2012 19:02 182 191 91 96.66666667 2 10/18/2012 19:03 174 183 83 10/18/2012 19:05 189 198 97 87 1 10/18/2012 19:10 54 63 85 10/18/2012 19:10 54 63 85 85 Now, what have I tried? I tried putting this into separate tables, queries and do some joins... Nothing works and I am very frustrated... I am not even sure if this could be done via the query. Asking for the expert help!

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  • inserting time delay with cocos2d

    - by KDaker
    I am trying to add several labels that appear sequentially with a time delay between each. The labels will display either 0 or 1 and the value is calculated randomly. I am running the following code: for (int i = 0; i < 6; i++) { NSString *cowryString; int prob = arc4random()%10; if (prob > 4) { count++; cowryString = @"1"; } else { cowryString = @"0"; } [self runAction:[CCSequence actions:[CCDelayTime actionWithDuration:0.2] ,[CCCallFuncND actionWithTarget:self selector:@selector(cowryAppearWithString:data:) data:cowryString], nil]]; } the method that makes the labels appear is this: -(void)cowryAppearWithString:(id)sender data:(NSString *)string { CCLabelTTF *clabel = [CCLabelTTF labelWithString:string fontName:@"arial" fontSize:70]; CGSize screenSize = [[CCDirector sharedDirector] winSize]; clabel.position = ccp(200.0+([cowries count]*50),screenSize.height/2); id fadeIn = [CCFadeIn actionWithDuration:0.5]; [clabel runAction:fadeIn]; [cowries addObject:clabel]; [self addChild:clabel]; } The problem with this code is that all the labels appear at the same moment with the same delay. I understand that if i use [CCDelayTime actionWithDuration:0.2*i] the code will work. But the problem is that i might also need to iterate this entire for loop and have the labels appear again after they have appeared the first time. how is it possible to have actions appear with delay and the actions dont always follow the same order or iterations???

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  • cURL/PHP Request Executes 50% of the Time

    - by makavelli
    After searching all over, I can't understand why cURL requests issued to a remote SSL-enabled host are successful only 50% or so of the time in my case. Here's the situation: I have a sequence of cURL requests, all of them issued to a HTTPS remote host, within a single PHP script that I run using the PHP CLI. Occasionally when I run the script the requests execute successfully, but for some reason most of the times I run it I get the following error from cURL: * About to connect() to www.virginia.edu port 443 (#0) * Trying 128.143.22.36... * connected * Connected to www.virginia.edu (128.143.22.36) port 443 (#0) * successfully set certificate verify locations: * CAfile: none CApath: /etc/ssl/certs * error:140943FC:SSL routines:SSL3_READ_BYTES:sslv3 alert bad record mac * Closing connection #0 If I try again a few times I get the same result, but then after a few tries the requests will go through successfully. Running the script after that again results in an error, and the pattern continues. Researching the error 'alert bad record mac' didn't give me anything helpful, and I hesitate to blame it on an SSL issue since the script still runs occasionally. I'm on Ubuntu Server 10.04, with php5 and php5-curl installed, as well as the latest version of openssl. In terms of cURL specific options, CURLOPT_SSL_VERIFYPEER is set to false, and both CURLOPT_TIMEOUT and CURLOPT_CONNECTTIMEOUT are set to 4 seconds. Further illustrating this problem is the fact that the same exact situation occurs on my Mac OS X dev machine - the requests only go through ~50% of the time.

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  • Encode_JSON Errors in Lasso 8.6.2 After Period of Time

    - by ATP_JD
    We are in the process of converting apps from Lasso 8 to Lasso 9, and as an intermediate step, have upgraded from 8.5.5 to 8.6.2 (which runs alongside 9 on our new box, in different virtual hosts). I am finding that with 8.6.2 we are getting a slew of errors on pages that call encode_json. The weird thing with these errors is that they don't start happening until some period of time after the site starts. Then, some hours later, all encode_json calls begin to fail with error messages like this: An error occurred while processing your request. Error Information Error Message: No tag, type or constant was defined under the name "?????????????????" with arguments: array: (pair: (-find)=([\x{0020}-\x{21}\x{23}-\x{5b}\x{5d}-\x{10fff}])), (r) at: onCompare with params: 'r' at: JSON with params: 'reload', -Options=array: (-Internal) at: JSON with params: @map: (reload)=(false), (tcstring)=(LZU), (timestring)=(10:42 AM&nbsp;&nbsp;&nbsp;1442Z) at: [...].lasso with params: 'pageloadtime'='1383038310' on line: 31 at position: 1 Error Code: -9948 (Yes, those Chinese(?) characters are in the error message.) I have removed the 8.5.5 encode_json tag from LassoStartup, so we are using the correct built-in method. The encode_json method fails for any and all parameters I throw at it from simple strings to arrays of maps. Upon restarting the site, encode_json resumes working for an hour or two, seemingly depending on load. On 8.5.5, we don't have this problem. Does anyone have experience with this issue? Any advice regarding trying the 8.5.5 tag swap encode_json to see if I can override the built-in method? Maybe it will work better? Thanks in advance for your time and assistance. -Justin

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  • Cake returned the time consumed in data lookup in JQuery Alert Box

    - by kwokwai
    Hi all, When I was doing some self-learning on JQuery Ajax in Cakephp, I found out some strange behaviour in the JQuery Alert Box. Here are a few lines of code of the JQuery Ajax I used: $(document).ready(function(){ $(document).change(function(){ var usr = $("#data\\[User\\]\\[name\\]").val(); $.post{"http://www.mywebsite.com/controllers/action/", usr, function(msg){alert(msg);} } }); }); The Alert box shows me a message returned from the Action: Helloworld <!--0.656s--> I am not sure why the number of time consumption was displayed in the Alert box, since it was not in my code as follows: function action($data=null){ $this->autoRender = false; $result2=$this->__avail($data); if($result2==1) {return "OK";} else {return "NOT";} } CakePHP rteurned some extra information in the Alert box. Later I altered a single line of code and tried out this instead, and the time consumption was not displayed on screen then: $(document).ready(function(){ $(document).change(function(){ var usr = $("#data\\[User\\]\\[name\\]").val(); $.post{"http://www.mywebsite.com/controllers/action/", usr, function(msg){$("#username").append('<span>'+msg+</span'>);} } }); });

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  • MATLAB, time match filter

    - by Paul
    OK, I am still getting the hang of MATLAB. I have two files in different format. One Excel file. data1.xls, size= 86400 X 62. It looks like: Date/Time par1 par2 par3 par4 par5 par6 par6 par7 par8 par9 08/02/09 00:06:45 0 3 27 9.9 -133.2 0 0 0 1 0 Another file, data2.csv, size = 144 X 27. (If nothing is missing.) It looks like: date time P01 P02 P03 P04 P05 P06 P07 P08 P09 P10 P11 8/16/2009 0:00 51 45 46 54 53 52 524 5 399 89 78 Now I am using Data10minAvg = mean(reshape(Data,300,144,62)); to get the 10 min average of the first Excel file. Now I need to match up that file I am making above with the .csv file. The problem is many timestamps are missing in the .csv file. How do I make data2.csv into a file of size 144 X 27, replacing the missing datestamps by rows of zero? It will really help me than compare data1.xls file with newdata2.csv.

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  • Big-Oh running time of code in Java (are my answers accurate

    - by Terry Frederick
    the Method hasTwoTrueValues returns true if at least two values in an array of booleans are true. Provide the Big-Oh running time for all three implementations proposed. // Version 1 public boolean has TwoTrueValues( boolean [ ] arr ) { int count = 0; for( int i = 0; i < arr. length; i++ ) if( arr[ i ] ) count++; return count >= 2; } // Version 2 public boolean hasTwoTrueValues( boolean [ ] arr ) { for( int i = 0; i < arr.length; i++ ) for( int j = i + 1; j < arr.length; j++ ) if( arr[ i ] && arr[ j ] ) return true; } // Version 3 public boolean hasTwoTrueValues( boolean [ ] arr ) { for( int i = 0; i < arr.length; i++ if( arr[ i ] ) for( int j = i + 1; j < arr.length; j++ ) if( arr[ j ] ) return true; return false; } For Version 1 I say the running time is O(n) Version 2 I say O(n^2) Version 3 I say O(n^2) I am really new to this Big Oh Notation so if my answers are incorrect could you please explain and help.

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  • Optimal (Time paradigm) solution to check variable within boundary

    - by kumar_m_kiran
    Hi All, Sorry if the question is very naive. I will have to check the below condition in my code 0 < x < y i.e code similar to if(x > 0 && x < y) The basic problem at system level is - currently, for every call (Telecom domain terminology), my existing code is hit (many times). So performance is very very critical, Now, I need to add a check for boundary checking (at many location - but different boundary comparison at each location). At very normal level of coding, the above comparison would look very naive without any issue. However, when added over my statistics module (which is dipped many times), performance will go down. So I would like to know the best possible way to handle the above scenario (kind of optimal way for limits checking technique). Like for example, if bit comparison works better than normal comparison or can both the comparison be evaluation in shorter time span? Other Info x is unsigned integer (which must be checked to be greater than 0 and less than y). y is unsigned integer. y is a non-const and varies for every comparison. Here time is the constraint compared to space. Language - C++. Now, later if I need to change the attribute of y to a float/double, would there be another way to optimize the check (i.e will the suggested optimal technique for integer become non-optimal solution when y is changed to float/double). Thanks in advance for any input. PS : OS used is SUSE 10 64 bit x64_64, AIX 5.3 64 bit, HP UX 11.1 A 64.

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  • Creation of AsyncTask taking too much time Android

    - by user2842342
    I am making a network call in an AsyncTask, but the problem i am facing is the amount of time it is taking to start the doInBackground method. Here is a part of my code: button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Log.d("Temp:",System.currentTimeMillis()+""); new Move().execute(); /*some other logic } } And my AsyncTask is: private class Move extends AsyncTask<Void, Void, Void> { @Override protected Void doInBackground(Void... temp) { Log.d("start:",System.currentTimeMillis()+""); gson.fromJson(Web.Request.get(some_URL),Void.class); Log.d("end:",System.currentTimeMillis()+""); return null; } } These are the logs i got: 32658-998/com.example.game D/temp:? 1408923006159 32658-998/com.example.game D/start:? 1408923035163 32658-998/com.example.game D/end:? 1408923035199 So actually it took almost 29 secs to reach the first line in doInBackground method, where as it took just 36 ms to finish the network call. I tried it many times, the time taken is almost in the same order. Is it possible to start the AsyncTask immediately? Or is there any other way to solve this problem.(other than a running a simple thread?) Thank you :)

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  • how to pass time Interval in list pref option

    - by user1748932
    <ListPreference android:entries="@array/listOptions2" android:entryValues="@array/listValues2" android:key="listprefrefresh" android:summary="set Refresh The Applciation" android:title="Set TIme Intervale" /> <item>10 </item> <item>30</item> </integer-array> <integer-array name="listValues2"> <item>10000</item> <item>30000</item> </integer-array> public static final String PREF_BEER_SIZE2 = "listprefrefresh"; Preference beerPref2 = (Preference) findPreference(PREF_BEER_SIZE2); beerPref2 .setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() { public boolean onPreferenceChange(Preference preference, Object newValue) { // TODO Auto-generated method stub final ListPreference listrefresh = (ListPreference) preference; final int idx = listrefresh .findIndexOfValue((String) newValue); if (idx == 0 ) { handler.post(timedTask); // } else if (idx == 1) { // System.out.println("2"); } return true; } }); This is my code i want Pass Time how can i implement right now? I am passing Integr value.please tell me

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  • Keeping the camera from going through walls in a first person game in Unity?

    - by Timothy Williams
    I'm using a modified version of the standard Unity First Person Controller. At the moment when I stand near walls, the camera clips through and lets me see through the wall. I know about camera occlusion and have implemented it in 3rd person games, but I have no clue how I'd accomplish this in a first person game, since the camera doesn't move from the player at all. How do other people accomplish this?

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  • New Oracle EM Book: "Oracle Enterprise Manager Grid Control Advanced OEM Techniques for the Real World" - First to include EM11g

    - by cristobal.soto(at)oracle.com
    The first book written about Enterprise Manager that covers the new Enterprise Manager Grid Control 11g which was released in April 2010 can be ordered now at a significant discount from http://www.rampant-books.com/book_1001_advanced_techniques_oem_grid_control.htmAbout the Author: Porus HavewalaPorus is a Senior Manager (Database Management) in the Enterprise Technology Program Office of Oracle Corporation based in Singapore. He has published numerous articles on Grid Control and RMAN on OTN, and created the world's first blog dedicated to Grid Control. Porus frequently speaks about Enterprise Manager at industry conferences and has created and executed an innovative program of seminars and workshops.

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  • Calgary .NET User Group &ndash; Entity Framework Code First - December 11th

    - by David Paquette
    I will be presenting at the Calgary .NET User Group on December 11th. We will start from scratch in this intro to Entity Framework Code First. We will build a simple application using ASP.NET MVC and Entity Framework and evolve the application to show how we can build scalable applications using Entity Framework Code First. Topics covered will include database initialization, code based migrations, performance profiling and performance tuning. Register at http://www.dotnetcalgary.com/

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  • in iOS7 how do you stop the First viewcontroller autorotating?

    - by uaka
    I have an app that just needs one screen to autorotate, the first and last screens should be portrait. I can get the last screen to stop rotating using: -(NSUInteger)supportedInterfaceOrientations { return UIInterfaceOrientationMaskPortrait; } But this does not work on the first screen, I am using a storyboard with a UINavigationController (I'm thinking that may have something to do with it?) Any help would be gratefully received. Thanks

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  • Is it better to learn the DOM or jQuery first?

    - by user1146440
    I have gotten very familiar with the core functionality of Javascript and now I am aiming at learning DOM manipulation. I have already thought of learning jQeury for this but I don't know if it is good idea to learning it before first getting familiar with the core functionality of the DOM. Should I first learn the core functionality of the DOM and then learn jQuery? If so, why? Or should I just go on ahead and learn jQuery?

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  • UpdatePanel, JavaScript postback and changing querystring at same time in SharePoint Search Page

    - by Lee Dale
    Hi Guys, Been tearing my hear out with this one. Let me see if I can explain: I have a SharePoint results page on which I have a Search Results Core WebPart. Now I want to change the parameter in the querystring when I postback the page so that the WebPart returns different results for each parameter e.g. the querystring will be interactivemap.aspx?k=Country:Romania this will filter the results for Romania. First issue is I want to do this with javascript so I call: document.getElementById('aspnetForm').action = "interactivemap.aspx?k=Country:" + country; Nothing special here but the reason I need to call from Javascript is there is also a flash applet on this page from which the Javascript calls originate. When the javascript calls are made the page needs to PostBack but not reload the flash applet. I turned to ASP.Net AJAX for this so I wrapped the search results webpart in an update panel. Now if I use a button within the UpdatePanel to postback the UpdatePanel behaves as expected and does a partial render of the search results webpart not reloading the flash applet. Problem comes because I need postback the page from javscript. I called __doPostBack() as I have used this successully in the past. It works on it's own but fails when I first call the above Javascript before the __doPostBack() (I also tried calling click() on a hidden button) the code for the page is at the bottom. I think the problem comes with the scriptmanager not allowing a partial render when the form post action has changed. My questions are. A) Is there some other way to change the search results webpart parameter without using the querystring. or B) Is there a way around changing the querystring when doing an AJAX postback and getting a partial render. <asp:Content ContentPlaceHolderID="PlaceHolderFullContent" runat="server"> function update(country) { //__doPostBack('ContentUpdatePanel', ''); //document.getElementById('aspnetForm').action = "interactivemap.aspx?k=ArticleCountry:" + country; document.getElementById('ctl00_PlaceHolderFullContent_UpdateButton').click(); } Romania <div class="firstDataTitle"> <div class="datatabletitleOuterWrapper"> <div class="datatabletitle"> <span>Content</span></div> </div> <div class="datatableWrapper"> <div class="dataHolderWrapper"> <div class="datatable"> <div> <div class="searchMain"> <div class="searchZoneMain"> <asp:UpdatePanel runat="server" id="ContentUpdatePanel" UpdateMode="Conditional"> <ContentTemplate> <WebPartPages:webpartzone runat="server" AllowPersonalization="false" title="<%$Resources:sps,LayoutPageZone_BottomZone%>" id="BottomZone" orientation="Vertical" QuickAdd-GroupNames="Search" QuickAdd-ShowListsAndLibraries="false"><ZoneTemplate></ZoneTemplate></WebPartPages:webpartzone> <asp:Button id="UpdateButton" name="UpdateButton" runat="server" Text="Update"/> </ContentTemplate> </asp:UpdatePanel> </div> </div> </div> </div> </div> </div>

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  • Ensuring a divs content has changed over time in Selenium

    - by Stewart Robinson
    I have a div that contains a slideshow. ( http://film.robinhoodtax.org/issues/education ) I am using Selenium to test it. So far I have been using the HTML/Selenium script below to validate that the slideshow is actually working. But my assertEval is failing. How can I correctly detect the slideshow and make sure it is moving?. You can see I've approached this by storing the HTML and waiting then trying again but it isn't working. <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> <head profile="http://selenium-ide.openqa.org/profiles/test-case"> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <link rel="selenium.base" href="" /> <title>New Test</title> </head> <body> <table cellpadding="1" cellspacing="1" border="1"> <thead> <tr><td rowspan="1" colspan="3">New Test</td></tr> </thead><tbody> <tr> <td>open</td> <td>/issues/education</td> <td></td> </tr> <tr> <td>waitForPageToLoad</td> <td></td> <td></td> </tr> <tr> <td>assertElementPresent</td> <td>css=div[id='views-nivo-slider-ImagesGallery-block_1']</td> <td></td> </tr> <tr> <td>storeHtmlSource</td> <td>css=div[id='views-nivo-slider-ImagesGallery-block_1']</td> <td>first</td> </tr> <tr> <td>pause</td> <td>3000</td> <td></td> </tr> <tr> <td>storeHtmlSource</td> <td>css=div[id='views-nivo-slider-ImagesGallery-block_1']</td> <td>second</td> </tr> <tr> <td>assertEval</td> <td>${first} == ${second}</td> <td>second</td> </tr> </tbody></table> </body> </html>

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  • Do i need a full time seo employee? [closed]

    - by user481913
    I need seo done for 1 site that's still new. It's a niche listings/ecommerce site. And i need to make a hiring decision for this - whether there's a need for a full time employee dedicated to seo or is part time or a contract sufficient? Here's some info and assumptions : 1)The site's dynamic - so perhaps all ON PAGE SEO - keyword research, page title, meta tags etc. could be built in programatically and is perhaps ONE TIME EFFORT. 2)Most(perhaps not all) ON PAGE SEO is taken care at the start or initially so doesn't need much time devotion later. 3)Most ON PAGE SEO for a DYNAMIC site is a programmer's job(as probably a seo employee doesn't understand programming) with some assistance from a seo employee for KEYWORD RESEARCH etc. So once built into the software, it DOESN'T NEED much effort on part of the seo employee in the later stages. 4)OFF PAGE SEO IS really where the seo employee would really spend most of his/her time - like build some links, write articles/blogs, directory submissions etc. So considering that there's just 1 site and that most effort for the seo employee is concenterated on OFF PAGE SEO, do i really need to hire someone Full Time? You're most welcome to add your own views and perspectives to this. It might help someone else as well in the future in their hiring decision.

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  • How do I interpolate air drag with a variable time step?

    - by Valentin Krummenacher
    So I have a little game which works with small steps, however those steps vary in time, so for example I sometimes have 10 Steps/second and then I have 20 Steps/second. This changes automatically depending on how many steps the user's computer can take. To avoid inaccurate positioning of the game's player object I use y=v0*dt+g*dt^2/2 to determine my objects y-position, where dt is the time since the last step, v0 is the velocity of my object in the beginning of my step and g is the gravity. To calculate the velocity in the end of a step I use v=v0+g*dt what also gives me correct results, independent of whether I use 2 steps with a dt of for example 20ms or one step with a dt of 40ms. Now I would like to introduce air drag. For simplicity's sake I use a=k*v^2 where a is the air drag's acceleration (I am aware that it would usually result in a force, but since I assume 1kg for my object's mass the force is the same as the resulting acceleration), k is a constant (in this case I'm using 0.001) and v is the speed. Now in an infinitely small time interval a is k multiplied by the velocity in this small time interval powered by 2. The problem is that v in the next time interval would depend on the drag of the last which again depends on the v of the last interval and so on... In other words: If I use a=k*v^2 I get different results for my position/velocity when I use 2 steps of 20ms than when I use one step of 40ms. I used to have this problem for my position too, but adding +g*dt^2/2 to the formula for my position fixed the problem since it takes into account that the position depends on the velocity which changes slightly in every infinitely small time interval. Does something like that exist for air drag too? And no, I dont mean anything like Adding air drag to a golf ball trajectory equation or similar, for that kind of method only gives correct results when all my steps are the same. (I hope you can understand my intermediate english, it's not my main language so I would like to say sorry for all the silly mistakes I might have made in my question)

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  • Extjs Date Time Picker ,HighLight particular Date instead of system date

    - by vineth
    Hi, How to highlight the particular date in extjs calender(Date Time Picker) control, As default it will highlight the system date when its shows, i need to set highlight date as sql server date. since it will be different. Is there any property or override method to change the highlight date.!!! Note: Only highlight in the calender not to set that value to text box.

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  • Using Google Maps API to get travel time data

    - by nibbo
    Hi! All the examples I've come across using google maps api seem to show a map of some kind. I would like to incorporate the data about the estimated travel time by car they give you when you ask for a road description from A to B into a site. And only that data. Is it possible without loading up a map for the end visitor? Thanks

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  • iPhone NSDate - get time in milliseconds and store in coredata

    - by satyam
    I'm implementing iphone app with coredata functionality. I've an attribute in entity "NSDate" which stores the date and time when the record is added. I'm adding records at a faster rate. About 1 record per 25 milli seconds I want to store the date along with milli seconds so that I can retrieve the data in descending order. How can I do this?

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