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  • Noob Droid Question regarding random number

    - by Pete Herbert Penito
    Brand new to droid programming, but would love to learn as much as possible, so I finally got my emulator working correctly, I even got a hello world button to work, I'm attempting to make this button display a random number, I've googled this and came up with this code: Random generator = new Random(); int n = generator.nextInt(n); I fixed the Random function by including some Random java utility. I'm assuming this code above goes in the .java file of the project, so my button code looks as follows (tested and works): PopUpText.makeText(v.getContext(), "Hello World", PopUpText.LENGTH_LONG).show(); I figured I could replace "Hello World" with n to display the number in the box, however the following error is stopping the compile: The local variable n may not have been initialized Any ideas why this is happening? Any advice would be hugely appreciated.

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  • Newbie C# Question about float/int/text type formatting

    - by user563501
    Hey everybody, I'm a total C# newb with a light (first year CS) background in Python. I wrote a console program in Python for doing marathon pace running calculations and I'm trying to figure out the syntax for this in C# using Visual Studio 2010. Here's a chunk of what I've got so far: string total_seconds = ((float.Parse(textBox_Hours.Text) * 60 * 60) + (float.Parse(textBox_Minutes.Text) * 60) + float.Parse(textBox_Seconds.Text)).ToString(); float secs_per_unit = ((float)(total_seconds) / (float)(textBox_Distance.Text)); float mins_per_unit = (secs_per_unit / 60); string pace_mins = (int)mins_per_unit.ToString(); string pace_secs = (float.Parse(mins_per_unit) - int.Parse(mins_per_unit) * 60).ToString(); textBox_Final_Mins.Text = pace_mins; textBox_Final_Secs.Text = pace_mins; Imagine you have a running pace of 8 minutes and 30 seconds per mile. secs_per_unit would be 510, mins_per_unit would be 8.5. pace_mins would simply be 8 and pace_secs would be 30. In Python I'd just convert variables from a float to a string to get 8 instead of 8.5, for example; hopefully the rest of the code gives you an idea of what I've been doing. Any input would be appreciated.

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  • Question about joins and table with Millions of rows

    - by xRobot
    I have to create 2 tables: Magazine ( 10 millions of rows with these columns: id, title, genres, printing, price ) Author ( 180 millions of rows with these columns: id, name, magazine_id ) . Every author can write on ONLY ONE magazine and every magazine has more authors. So if I want to know all authors of Motors Magazine, I have to use this query: SELECT * FROM Author, Magazine WHERE ( Author.id = Magazine.id ) AND ( genres = 'Motors' ) The same applies to Printing and Price column. To avoid these joins with tables of millions of rows, I thought to use this tables: Magazine ( 10 millions of rows with this column: id, title, genres, printing, price ) Author ( 180 millions of rows with this column: id, name, magazine_id, genres, printing, price ) . and this query: SELECT * FROM Author WHERE genres = 'Motors' Is it a good approach ? I can use Postgresql or Mysql.

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  • sql join question, how to select when value not in a set of values

    - by Elliott
    I have two tables, table1 and table2. Table1 is in a one to many relationship with table2 (one row in table1 maps to many rows in table2). There is a field in table2 called code. If none of the values of code in table2 equal some set of values (say 1, 2, and 3), I want to select the value in table1. I'm not sure how to write this kind of join. Assume the primary key in table1 is called id and the foreign key to which it maps is called did. Can you tell me how to write this kind of join? Thanks, Elliott

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  • question about PORT

    - by user222820
    I have written a program in C# that sends text to COMx. I wish to test it using HyperTerminal, meaning I want to read the text that I send with my program. When I set the WAIT FOR CALL in HyperTerminal, my program is refused access to the given port. How can I test my program? Is it possible?

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  • Database design question (Book Trading System)

    - by Paul
    Hello all! I´m developing a Book Trading System... The user will input your Book to trading... I already have a table tblBook with "all" existing books ... So the user will select one book from that list and fill the book´s CONDITIONS and Edition... So, what is a good Database design to tha case? tblBook = All books tblUserBook = All User Books And making tblUserBook to inheritance tblBook? Thanks

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  • Question regarding MySQL indices and their functionality

    - by user281434
    Hi Say I have an ordinary table in my db like so ---------------------------- | id | username | password | ---------------------------- | 24 | blah | blah | ---------------------------- A primary key is assigned to the id column. Now when I run a Mysql query like this: SELECT id FROM table WHERE username = 'blah' LIMIT 1 Does that primary key index even help? If I am telling it to match usernames, then shouldn't the username column be indexed instead? Thanks for your time

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  • OWL inferencing question

    - by user439170
    I am using the Jena semantic web framework version 2.6.3. I have code that creates a model with owl inferencing and then adds the following triples: [:bnode-3 rdf:type owl:Restriction] [:bnode-3 owl:onProperty :offspringOf] [:bnode-3 owl:someValuesFrom :Person] [:bnode-3 rdfs:subClassOf :Person] bnode-3 is supposed to be a restriction class which, for example, would contain :joe if :bob is a :Person and the following triple were asserted: [:joe :offspringOf :bob]. Then, since the restriction class is a subclass of Person, :joe would also be a person. And, in fact, this works. Whats confusing to me is that after I assert just the 4 triples at the top of this post, the inferencer creates a blank node which is a Person. In other words, the following triple is now in the model: [_:b0 rdf:type :Person] I don't understand why it would do this. Any help in understanding this would be greatly appreciated. Thanks. Kent.

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  • Basic question on retain/release semantics from Apple's reference library

    - by davetron5000
    I have done Objective-C way back when, and have recently (i.e. just now) read the documentation on Apple's site regarding the use of retain and release. However, there is a bit of code in their Creating an iPhone Application page that has me a bit confused: - (void)setUpPlacardView { // Create the placard view -- it calculates its own frame based on its image. PlacardView *aPlacardView = [[PlacardView alloc] init]; self.placardView = aPlacardView; [aPlacardView release]; // What effect does this have on self.placardView?! placardView.center = self.center; [self addSubview:placardView]; } Not seeing the entire class, it seems that self.placardView is also a PlacardView * and the assignment of it to aPlacardView doesn't seem to indicate it will retain a reference to it. So, it appears to me that the line I've commented ([aPlacardView release];) could result in aPlacardView having a retain count of 0 and thus being deallocated. Since self.placardView points to it, wouldn't that now point at deallocated memory and cause a problem?

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  • Question about how to implement a c# host application with a plugin-like architecture

    - by devoured elysium
    I want to have an application that works as a Host to many other small applications. Each one of those applications should work as kind of plugin to this main application. I call them plugins not in the sense they add something to the main application, but because they can only work with this Host application as they depend on some of its services. My idea was to have each of those plugins run in a different app domain. The problem seems to be that my host application should have a set of services that my plugins will want to use and from what is my understanding making data flow in and out from different app domains is not that great of a thing. On one hand I'd like them to behave as stand-alone applications(although, as I said, they need to use lots of times the host application services), but on the other hand I'd like that if any of them crashes, my main application wouldn't suffer from it. What is the best (.NET) approach to this kind of situation? Make them all run on the same AppDomain but each one in a different Thread? Use different AppDomains? One for each "plugin"? How would I make them communicate with the Host Application? Any other way of doing this? Although speed is not an issue here, I wouldn't like for function calls to be that much slower than they are when we're working with just a regular .NET application. Thanks

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  • SQL CASE Question

    - by docsql
    Hiya, I dont know if this can be done but i'd though i'd ask. What I want to do is have a case statement query and if a 1 begin another action. if 0 dont do anything. For Example select CASE WHEN client.deathofdeath = yes THEN 1 do another select in here (which is another table) Else 0 End AS DeathDate From Client client Can this be done?

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  • Two part question about submitting bluetooth-enabled apps for the iPhone

    - by Kyle
    I have a couple questions about submitting blue-tooth enabled apps on the iPhone. I want to first say that bluetooth is merely an option in the application. The application does not completely rely on bluetooth as there are many modes the user can go in. First, do they require you to have the "peer-peer" key set in UIRequiredDeviceCapabilities even if bluetooth interface options can be disabled or hidden for non-bluetooth enabled devices? Basically, it's just an OPTION in the game and there are many other modes the player can play.. Does Apple not allow you to do that? I'm just curious, because it seems like something they would do. Adding to that, how do you check for it's functionality at runtime? In essence, how do you check UIRequiredDeviceCapabilities at runtime. I'm aware of checking iPhone device types, so would that be a proper way of going about it? I'm also sort of unaware which devices can run bluetooth gamekit, there doesn't seem to be a proper reference at the SDK site, or I'm unable to find it. Thanks for reading! [edit] I can confirm the existance of somebody rejected for submitting a bluetooth enabled app which didn't work on a iPhone 2G.. Of course, they didn't say if that was the MAIN function of the app, though.

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  • question about LSD radix sort

    - by davit-datuashvili
    hello i have following code public class LSD{ public static int R=1<<8; public static int bytesword=4; public static void radixLSD(int a[],int l,int r){ int aux[]=new int[a.length]; for (int d=bytesword-1;d>=0;d--){ int i, j; int count[]=new int[R+1]; for ( j=0;j<R;j++) count[j]=0; for (i=l;i<=r;i++) count[digit(a[i],d)+1]++; for (j=1;j<R;j++) count[j]+=count[j-1]; for (i=l;i<=r;i++) aux[count[digit(a[i],d)]++]=a[i]; for (i=l;i<=r;i++) a[i]=aux[i-1]; } } public static void main(String[]args){ int a[]=new int[]{3,6,5,7,4,8,9}; radixLSD(a,0,a.length-1); for (int i=0;i<a.length;i++){ System.out.println(a[i]); } } public static int digit(int n,int d){ return (n>>d)&1; } } but it show me mistake java.lang.ArrayIndexOutOfBoundsException: -1 at LSD.radixLSD(LSD.java:19) at LSD.main(LSD.java:29) please help me

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  • Simple IF statement question

    - by JGreig
    How can I simply the below if statements? if ( isset(var1) & isset(var2) ) { if ( (var1 != something1) || (var2 != something2) ) { // ... code ... } } Seems like this could be condensed to only one IF statement but am not certain if I'd use an AND or OR

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  • C question on functions

    - by benjamin button
    some times i see that functions are defined as below: read_dir(dir) char *dir; { DIR * dirp; struct dirent *d; /* open directory */ dirp = opendir(dir); ......... so on here what is the importance of the statement char *dir; what is the intension behind declaring the pointer soon after the function name and then starting the function body.

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  • Python decorator question

    - by nsharish
    decorator 1: def dec(f): def wrap(obj, *args, **kwargs): f(obj, *args,**kwargs) return wrap decorator 2: class dec: def __init__(self, f): self.f = f def __call__(self, obj, *args, **kwargs): self.f(obj, *args, **kwargs) A sample class, class Test: @dec def disp(self, *args, **kwargs): print(*args,**kwargs) The follwing code works with decorator 1 but not with decorator 2. a = Test() a.disp("Message") I dont understand why decorator 2 is not working here. Can someone help me with this?

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  • Operating system scheduler question

    - by ual
    I recently asked myself: If a program, like Mozilla Firefox for example, is started - the control must be somehow given to it. But when the program crashes, why doesn't my whole system crash like in early Windows version? How can Windows take back the control from the program, or even not give it to it fully? (Note: This is not my homework; I go to school but in my informatics class are really only guys that would answer with "Can I eat that?" when I ask them about kernels. Same with my teacher.)

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  • Question about best practices and Macros from the book 'C++ Coding Standards'

    - by Victor T.
    From Herb Sutter and Andrei Alexandrescu's 'C++ Coding Standards', Item 16: Avoid Macros under Exceptions for this guideline they wrote: For conditional compilation (e.g., system-dependent parts), avoid littering your code with #ifdefs. Instead, prefer to organize code such that the use of macros drives alternative implementations of one common interface, and then use the interface throughout. I'm having trouble understanding exactly what they mean by this. How can you drive alternate implementations without the use of #ifdef conditional compile macro directives? Can someone provide an example to help illustrate what's being proposed by the above paragraph? Thanks

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  • NSString stringWithFormat question

    - by John Smith
    I am trying to build a small table using NSString. I cannot seem to format the strings properly. Here is what I have [NSString stringWithFormat:@"%8@: %.6f",e,v] where e is an NSString from somewhere else, and v is a float. What I want is output something like this: Grapes: 20.3 Pomegranates: 2.5 Oranges: 15.1 What I get is Grapes:20.3 Pomegranates:2.5 Oranges:15.1 How can I fix my format to do something like this?

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  • Operating system question

    - by ual
    I recently asked myself: If a program, like Mozilla Firefox for example, is started - the control must be somehow given to it. But when the program crashes, why doesn't my whole system crash like in early Windows version? How can Windows take back the control from the program, or even not give it to it fully? (Note: This is not my homework; I go to school but in my informatics class are really only guys that would answer with "Can I eat that?" when I ask them about kernels. Same with my teacher.)

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  • question about python COM programming

    - by usfree74
    Hey, I am trying to get the Dispatch object of IHTMLDocument3, so I wrote the following code wo = pythoncom.New('InternetExplorer.Application') wo.QueryInterface('{3050F673-98B5-11CF-BB82-00AA00BDCE0B}') But got the following error: pywintypes.com_error: (-2147467262, 'No such interface supported', None, None) Any idea on how to address this problem? Thanks, xin

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  • Question about the lifecycle of a simple Android application

    - by jul
    Hi, I've got a simple application with 3 activities: -the first contains a search box which calls a web service and show the results (restaurants) below in a listview -when a restaurant is clicked another activity is started showing the description of the restaurant and a button "show map" -when the button "show map" is clicked, guess what, the map is shown in a third activity. All the data is loaded in the first activity by a web service (restaurant descriptions and coordinates), and data required by each activity is passed in a bundle using "intent.putExtra". Now everything seems to run smoothly when clicking on the back button (eg. clicking on the back button from the map resumes the "restaurant description" activity with all data set properly), while I haven't done anything about the lifecycle yet. Why? Are all variables saved automatically? Should I use onSaveInstanceState() and onRestoreInstanceState() anyway? Thanks Jul

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  • javascript and extJs - scope question

    - by ben
    Hi guys, I got a little scope related problem with some js code, maybe somebody can explain to me what I'm making wrong: I'm using extJs and got this snippet: Ext.onReady(function(){ // Form for filter selection var formFilter = new Ext.FormPanel({ // ... items: [ cbGroup = new Ext.form.ComboBox({ fieldLabel: 'Group', store: dsGroups, displayField: 'name', valueField: 'number', emptyText : '- Please choose a group -', listeners:{ 'select': function() { alert(cbGroup.selectedIndex +' '+this.selectedIndex); } } }) ] }); }); The problem: When I access the combobox over 'this' within the listener function, I get the correct result for the selectIndex property. When I access the combobox over it's var name, I allways get the result '-1'. Thank a lot for your help!

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