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  • Interpreted languages: The higher-level the faster?

    - by immersion
    I have designed around 5 experimental languages and interpreters for them so far, for education, as a hobby and for fun. One thing I noticed: The assembly-like language featuring only subroutines and conditional jumps as structures was much slower than the high-level language featuring if, while and so on. I developed them both simultaneously and both were interpreted languages. I wrote the interpreters in C++ and I tried to optimize the code-execution part to be as fast as possible. My hypothesis: In almost all cases, performance of interpreted languages rises with their level (high/low). Am I basically right with this? (If not, why?)

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  • Get information from a higher class?

    - by Clint Davis
    I don't know really how to word the question so please bear with me... I have 3 classes: Server, Database, and Table. Each class has a "Name" property. How I want it to work is that each server can have multiple databases and each database can have multiple tables. So in the Server class I have this property. Private _databases As List(Of Database) Public Property Databases() As List(Of Database) Get Return _databases End Get Set(ByVal value As List(Of Database)) _databases = value End Set End Property And I have something similar in the Database class for the tables. This works fine now because I can do something like this to get all the databases in the server. For Each db In s.Databases 's being the server object Debug.Print(db.Name) Next I would like to expand these classes. I want the server class to handle all the connection information and I would like the other classes to use the server class's connection information in them. For example, I setup a server class and set the connection string to the server. Then I want the database class to use serverclass.connectionstring property to connect to the server and get a list of all the databases. But I want to keep that code in the database class. How can I do this? I've attached some code of what I want to do. Public Class Server Private _name As String Public Property Name() As String Get Return _name End Get Set(ByVal value As String) _name = value End Set End Property Private _databases As List(Of Database) Public Property Databases() As List(Of Database) Get Return _databases End Get Set(ByVal value As List(Of Database)) _databases = value End Set End Property End Class '-----New class Public Class Database Private _name As String Public Property Name() As String Get Return _name End Get Set(ByVal value As String) _name = value End Set End Property Private _tables As List(Of Table) Public Property Tables() As List(Of Table) Get Return _tables End Get Set(ByVal value As List(Of Table)) _tables = value End Set End Property 'This is where I need help! Private Sub LoadTables () dim connectionstring as string = server.connectionstring 'Possible? 'Do database stuff End Class Thanks for reading!

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  • ORDERBY "human" alphabetical order using SQL string manipulation

    - by supertrue
    I have a table of posts with titles that are in "human" alphabetical order but not in computer alphabetical order. These are in two flavors, numerical and alphabetical: Numerical: Figure 1.9, Figure 1.10, Figure 1.11... Alphabetical: Figure 1A ... Figure 1Z ... Figure 1AA If I orderby title, the result is that 1.10-1.19 come between 1.1 and 1.2, and 1AA-1AZ come between 1A and 1B. But this is not what I want; I want "human" alphabetical order, in which 1.10 comes after 1.9 and 1AA comes after 1Z. I am wondering if there's still a way in SQL to get the order that I want using string manipulation (or something else I haven't thought of). I am not an expert in SQL, so I don't know if this is possible, but if there were a way to do conditional replacement, then it seems I could impose the order I want by doing this: delete the period (which can be done with replace, right?) if the remaining figure number is more than three characters, add a 0 (zero) after the first character. This would seem to give me the outcome I want: 1.9 would become 109, which comes before 110; 1Z would become 10Z, which comes before 1AA. But can it be done in SQL? If so, what would the syntax be? Note that I don't want to modify the data itself—just to output the results of the query in the order described. This is in the context of a Wordpress installation, but I think the question is more suitably an SQL question because various things (such as pagination) depend on the ordering happening at the MySQL query stage, rather than in PHP.

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  • Create ordering in a MySQL table without using a number (because then it's hard to put something in

    - by user347256
    I have a long list of items (say, a few million items) in a mysql table, let's call it mytable and it has the field mytable.itemid. The items are given an order, and can be re=ordered by the user by drag and drop. If I add a field called mytable.order and just put numbers in them, it creates problems: what if I want to move an item between 2 other items? Then all the order fields have to be updated? That seems like a nightmare. Is there a (scalable) way to add order to a table that is different from just giving every item a number, order by that, and do loads of SQL queries everytime the order is changed?

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  • Accessing a Class Member from a First-Class Function

    - by dbyrne
    I have a case class which takes a list of functions: case class A(q:Double, r:Double, s:Double, l:List[(Double)=>Double]) I have over 20 functions defined. Some of these functions have their own parameters, and some of them also use the q, r, and s values from the case class. Two examples are: def f1(w:Double) = (d:Double) => math.sin(d) * w def f2(w:Double, q:Double) = (d:Double) => d * q * w The problem is that I then need to reference q, r, and s twice when instantiating the case class: A(0.5, 1.0, 2.0, List(f1(3.0), f2(4.0, 0.5))) //0.5 is referenced twice I would like to be able to instantiate the class like this: A(0.5, 1.0, 2.0, List(f1(3.0), f2(4.0))) //f2 already knows about q! What is the best technique to accomplish this? Can I define my functions in a trait that the case class extends? EDIT: The real world application has 7 members, not 3. Only a small number of the functions need access to the members. Most of the functions don't care about them.

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  • Oracle pl\sql question for my homework in oracle 11G class [migrated]

    - by Bjolds
    I am new to oracle 11G programming and i have run into a tough situation with pl\sql funtions and automation. I ame unsure how to create the function for the automation of Registration system for a College registration system. Here is what i want to do. I want to automate the registrations system so that it automaticly registers students. Then I want a procedure to automate the grading system. I have included the code that i am written to make most of this assignment work which it does but unsure how to incorporate Pl\SQL automated fuctions for the registrations system, and the grading system. So Any help or Ideas I would greatly appreciate please. set Linesize 250 set pagesize 150 drop table student; drop table faculty; drop table Course; drop table Section; drop table location; DROP TABLE courseInstructor; DROP TABLE Registration; DROP TABLE grade; create table student( studentid number(10), Lastname varchar2(20), Firstname Varchar2(20), MI Char(1), address Varchar2(20), city Varchar2(20), state Char(2), zip Varchar2(10), HomePhone Varchar2(10), Workphone Varchar2(10), DOB Date, Pin VARCHAR2(10), Status Char(1)); ALTER TABLE Student Add Constraint Student_StudentID_pk Primary Key (studentID); Insert into student values (1,'xxxxxxxx','xxxxxxxxxx','x','xxxxxxxxxxxxxxx','Columbus','oh','44159','xxx-xxx-xxxx','xxx-xxx-xxxx','06-Mar-1957','1211','c'); create table faculty( FacultyID Number(10), FirstName Varchar2(20), Lastname Varchar2(20), MI Char(1), workphone Varchar2(10), CellPhone Varchar2(10), Rank Varchar2(20), Experience Varchar2(10), Status Char(1)); ALTER TABLE Faculty ADD Constraint Faculty_facultyId_PK PRIMARY KEY (FacultyID); insert into faculty values (1,'xxx','xxxxxxxxxxxx',xxx-xxx-xxxx','xxx-xxx-xxxx','professor','20','f'); create table Course( CourseId number(10), CourseNumber Varchar2(20), CourseName Varchar(20), Description Varchar(20), CreditHours Number(4), Status Char(1)); ALTER TABLE Course ADD Constraint Course_CourseID_pk PRIMARY KEY(CourseID); insert into course values (1,'cit 100','computer concepts','introduction to PCs','3.0','o'); insert into course values (2,'cit 101','Database Program','Database Programming','4.0','o'); insert into course values (3,'Math 101','Algebra I','Algebra I Concepts','5.0','o'); insert into course values (4,'cit 102a','Pc applications','Aplications 1','3.0','o'); insert into course values (5,'cit 102b','pc applications','applications 2','3.0','o'); insert into course values (6,'cit 102c','pc applications','applications 3','3.0','o'); insert into course values (7,'cit 103','computer concepts','introduction systems','3.0','c'); insert into course values (8,'cit 110','Unified language','UML design','3.0','o'); insert into course values (9,'cit 165','cobol','cobol programming','3.0','o'); insert into course values (10,'cit 167','C++ Programming 1','c++ programming','4.0','o'); insert into course values (11,'cit 231','Expert Excel','spreadsheet apps','3.0','o'); insert into course values (12,'cit 233','expert Access','database devel.','3.0','o'); insert into course values (13,'cit 169','Java Programming I','Java Programming I','3.0','o'); insert into course values (14,'cit 263','Visual Basic','Visual Basic Prog','3.0','o'); insert into course values (15,'cit 275','system analysis 2','System Analysis 2','3.0','o'); create table Section( SectionID Number(10), CourseId Number(10), SectionNumber VarChar2(10), Days Varchar2(10), StartTime Date, EndTime Date, LocationID Number(10), SeatAvailable Number(3), Status Char(1)); ALTER TABLE Section ADD Constraint Section_SectionID_PK PRIMARY KEY(SectionID); insert into section values (1,1,'18977','r','21-Sep-2011','10-Dec-2011','1','89','o'); create table Location( LocationId Number(10), Building Varchar2(20), Room Varchar2(5), Capacity Number(5), Satus Char(1)); ALTER TABLE Location ADD Constraint Location_LocationID_pk PRIMARY KEY (LocationID); insert into Location values (1,'Clevleand Hall','cl209','35','o'); insert into Location values (2,'Toledo Circle','tc211','45','o'); insert into Location values (3,'Akron Square','as154','65','o'); insert into Location values (4,'Cincy Hall','ch100','45','o'); insert into Location values (5,'Springfield Dome','SD','35','o'); insert into Location values (6,'Dayton Dorm','dd225','25','o'); insert into Location values (7,'Columbus Hall','CB354','15','o'); insert into Location values (8,'Cleveland Hall','cl204','85','o'); insert into Location values (9,'Toledo Circle','tc103','75','o'); insert into Location values (10,'Akron Square','as201','46','o'); insert into Location values (11,'Cincy Hall','ch301','73','o'); insert into Location values (12,'Dayton Dorm','dd245','57','o'); insert into Location values (13,'Springfield Dome','SD','65','o'); insert into Location values (14,'Cleveland Hall','cl241','10','o'); insert into Location values (15,'Toledo Circle','tc211','27','o'); insert into Location values (16,'Akron Square','as311','28','o'); insert into Location values (17,'Cincy Hall','ch415','73','o'); insert into Location values (18,'Toledo Circle','tc111','67','o'); insert into Location values (19,'Springfield Dome','SD','69','o'); insert into Location values (20,'Dayton Dorm','dd211','45','o'); Alter Table Student Add Constraint student_Zip_CK Check(Rtrim (Zip,'1234567890-') is null); Alter Table Student ADD Constraint Student_Status_CK Check(Status In('c','t')); Alter Table Student ADD Constraint Student_MI_CK2 Check(RTRIM(MI,'abcdefghijklmnopqrstuvwxyz')is Null); Alter Table Student Modify pin not Null; Alter table Faculty Add Constraint Faculty_Status_CK Check(Status In('f','a','i')); Alter table Faculty ADD Constraint Faculty_Rank_CK Check(Rank In ('professor','doctor','instructor','assistant','tenure')); Alter table Faculty ADD Constraint Faculty_MI_CK2 Check(RTRIM(MI,'abcdefghijklmnopqrstuvwxyz')is Null); Update Section Set Starttime = To_date('09-21-2011 6:00 PM', 'mm-dd-yyyy hh:mi pm'); Update Section Set Endtime = To_date('12-10-2011 9:50 PM', 'mm-dd-yyyy hh:mi pm'); alter table Section Add Constraint StartTime_Status_CK Check (starttime < Endtime); Alter Table Section Add Constraint Section_StartTime_ck check (StartTime < EndTime); Alter Table Section ADD Constraint Section_CourseId_FK FOREIGN KEY (CourseID) References Course(CourseId); Alter Table Section ADD Constraint Section_LocationID_FK FOREIGN KEY (LocationID) References Location (LocationId); Alter Table Section ADD Constraint Section_Days_CK Check(RTRIM(Days,'mtwrfsu')IS Null); update section set seatavailable = '99'; Alter Table Section ADD Constraint Section_SeatsAvailable_CK Check (SeatAvailable < 100); Alter Table Course Add Constraint Course_CreditHours_ck check(CreditHours < = 6.0); update location set capacity = '99'; Alter Table Location Add Constraint Location_Capacity_CK Check(Capacity < 100); Create Table Registration ( StudentID Number(10), SectionID Number(10), Constraint Registration_pk Primary key (studentId, Sectionid)); Insert into registration values (1, 2); Insert into Registration values (2, 3); Insert into registration values (3, 4); Insert into registration values (4, 5); Insert into registration values (5, 6); Insert into registration values (6, 7); Insert into registration values (7, 8); Insert into registration values (8, 9); insert into registration values (9, 10); insert into registration values (10, 11); insert into registration values (9, 12); insert into registration values (8, 13); insert into registration values (7, 14); insert into registration values (6, 15); insert into registration values (5, 17); insert into registration values (4, 18); insert into registration values (3, 19); insert into registration values (2, 20); insert into registration values (1, 21); insert into registration values (2, 22); insert into registration values (3, 23); insert into registration values (4, 24); insert into registration values (5, 25); Insert into registration values (6, 24); insert into registration values (7, 23); insert into registration values (8, 22); insert into registration values (9, 21); insert into registration values (10, 20); insert into registration values (9, 19); insert into registration values (8, 17); Create Table courseInstructor( FacultyID Number(10), SectionID Number(10), Constraint CourseInstructor_pk Primary key (FacultyId, SectionID)); insert into courseInstructor values (1, 1); insert into courseInstructor values (2, 2); insert into courseInstructor values (3, 3); insert into courseInstructor values (4, 4); insert into courseInstructor values (5, 5); insert into courseInstructor values (5, 6); insert into courseInstructor values (4, 7); insert into courseInstructor values (3, 8); insert into courseInstructor values (2, 9); insert into courseInstructor values (1, 10); insert into courseInstructor values (5, 11); insert into courseInstructor values (4, 12); insert into courseInstructor values (3, 13); insert into courseInstructor values (2, 14); insert into courseInstructor values (1, 15); Create table grade( StudentID Number(10), SectionID Number(10), Grade Varchar2(1), Constraint grade_pk Primary key (StudentID, SectionID)); CREATE OR REPLACE TRIGGER TR_CreateGrade AFTER INSERT ON Registration FOR EACH ROW BEGIN INSERT INTO grade (SectionID,StudentID,Grade) VALUES(:New.SectionID,:New.StudentID,NULL); END TR_createGrade; / CREATE OR REPLACE FORCE VIEW V_reg_student_course AS SELECT Registration.StudentID, student.LastName, student.FirstName, course.CourseName, Registration.SectionID, course.CreditHours, section.Days, TO_CHAR(StartTime, 'MM/DD/YYYY') AS StartDate, TO_CHAR(StartTime, 'HH:MI PM') AS StartTime, TO_CHAR(EndTime, 'MM/DD/YYYY') AS EndDate, TO_CHAR(EndTime, 'HH:MI PM') AS EndTime, location.Building, location.Room FROM registration, student, section, course, location WHERE registration.StudentID = student.StudentID AND registration.SectionID = section.SectionID AND section.LocationID = location.LocationID AND section.CourseID = course.CourseID; CREATE OR REPLACE FORCE VIEW V_teacher_to_course AS SELECT courseInstructor.FacultyID, faculty.FirstName, faculty.LastName, courseInstructor.SectionID, section.Days, TO_CHAR(StartTime, 'MM/DD/YYYY') AS StartDate, TO_CHAR(StartTime, 'HH:MI PM') AS StartTime, TO_CHAR(EndTime, 'MM/DD/YYYY') AS EndDate, TO_CHAR(EndTime, 'HH:MI PM') AS EndTime, location.Building, location.Room FROM courseInstructor, faculty, section, course, location WHERE courseInstructor.FacultyID = faculty.FacultyID AND courseInstructor.SectionID = section.SectionID AND section.LocationID = location.LocationID AND section.CourseID = course.CourseID; SELECT * FROM V_reg_student_course; SELECT * FROM V_teacher_to_course;

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  • How do I Fix SQL Server error: Order by items must appear in the select list if Select distinct is s

    - by Paula DiTallo 2007-2009 All Rights Reserved
    There's more than one reason why you may receive this error, but the most common reason is that your order by statement column list doesn't correlate with the values specified in your column list when you happen to be using DISTINCT. This is usually easy to spot and resolve. A more obscure reason may be that you are using a function around one of the selected columns --but omitting to use the same function around the same selected column name in the order by statement. Here's an example:   select distinct upper(columnA)   from [evaluate].[testTable]    order by columnA  asc   This statement will cause the "Order by items must appear in the select list if SELECT DISTINCT is specified."  error to appear not because distinct was used, but because the order by statement did not utilize the upper() fundtion around colunnA.  To correct this error, do this: select distinct upper(columnA)   from [evaluate].[testTable]    order by upper(columnA) asc

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  • What's the best way to manage list item sort order with Drag & Drop UI?

    - by Reddy S R
    I have a list of Students that I should display to user on a web page in tabular format. The items are stored in DB along with SortOrder information. On the web page, user can rearrange the list order by dragging and dropping the items to their desired sort order, similar to this post. Below is a screenshot of my test page. In the above example, each row has sort order info attached to it. When I drop John Doe (Student Id 10) above the Student Id 1 row, the list order should now be: 2, 10, 1, 8, 11. What's the optimistic (less resource hungry) way to store and update Sort Order information? My only idea for now is, for every change in the list's sort order, every object's SortOrder value should be updated, which in my opinion is very resource hungry. Just FYI: I might have at most 25 rows in my table.

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  • Drawing Flowchart for function calculate a number in the Fibonacci Series

    - by truongvan
    I'm trying make Flowchart for function calculate a number in the Fibonacci Series. But It looks like not right. I don't how draw the recursive function. Please help me how to fix it. My flowchart: DIA This is my code: #include <iostream> using namespace std; long long Fibonacci(int input); int main() { cout << "Input Fibonacci Index number: "; int Index = 0; cin >> Index; cout << Fibonacci(i) << endl; return 0; } long long Fibonacci(int input) { if (input < 2) return input; else { return Fibonacci(input - 1) + Fibonacci(input - 2); } }

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  • What triggered the popularity of lambda functions in modern programming languages?

    - by Giorgio
    In the last few years anonymous functions (AKA lambda functions) have become a very popular language construct and almost every major / mainstream programming language has introduced them or is planned to introduce them in an upcoming revision of the standard. Yet, anonymous functions are a very old and very well-known concept in Mathematics and Computer Science (invented by the mathematician Alonzo Church around 1936, and used by the Lisp programming language since 1958, see e.g. here). So why didn't today's mainstream programming languages (many of which originated 15 to 20 years ago) support lambda functions from the very beginning and only introduced them later? And what triggered the massive adoption of anonymous functions in the last few years? Is there some specific event, new requirement or programming technique that started this phenomenon?

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  • Dual-boot computer won't boot without external hard drive

    - by FrankP
    I have Ubuntu loaded on my external HDD. I tried to unplug the external drive so that this way I could run Windows as the default OS to boot when the computer turns on, but it gives me an error. I need to know how I can make it so that when my computers boots it stops saying Error: no such device: (a whole bunch of numbers and letters) then it says grub rescue>_. If I plug the external HDD in, and I let Ubuntu run the boot process, then it gives me a list of OS's/ HDD's to choose from and Windows 7 is there. The only problem is that I want Windows be my default OS, not the other way around. P.S. I have found that I dislike Ubuntu because I can't even figure out how to install the necessary programs to learn how to start writing Ruby On Rails. So installing it was a waste of my time, in my opinion. Now that I have it on the external hard drive, I will leave it installed though. I just dont want to have to keep that external drive plugged in to my computer all the time. Thank you a ton to whoever can help me! Thank you for the detail'd instructions. I am doing my best to follow you and it makes sense when I read it but, Rescatux is not doing what you said it would. None of the options you said would appear are not there. On my screen there is 4 options when MBR run's none look familiar and when I picked the best possible option based on my educated guesses it said success. I tried to restart my computer and it said Please insert windows recovery disc and hit enter. Problem being I don't have the windows recovery disc. I bought my computer from a local Computer tec and he loads windows on it for you. I have no time to run my compute over to him as sunday is my only day free. I think that I just wrecked my computer in the process of this attempted fix windows refuses to boot now WITH or WITHOUT the HDD. Please help this is getting out of hand

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  • Is it bad practice to output from within a function?

    - by Nick
    For example, should I be doing something like: <?php function output_message($message,$type='success') { ?> <p class="<?php echo $type; ?>"><?php echo $message; ?></p> <?php } output_message('There were some errors processing your request','error'); ?> or <?php function output_message($message,$type='success') { ob_start(); ?> <p class="<?php echo $type; ?>"><?php echo $message; ?></p> <?php return ob_get_clean(); } echo output_message('There were some errors processing your request','error'); ?> I understand they both achieve the same end result, but are there benefits doing one way over the other? Or does it not even matter?

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  • The old "do as I say, not as I do" problem

    - by AaronBertrand
    Microsoft is often considered a leader, an innovator, a trend-setter. The same could be said for Apple, Google, and a host of other tech companies. And each of those has its set of critics as well, who think that the company is the opposite - or worse. Some people think it is a good idea to model their own code, architecture or applications after things that these companies have done, but this is not always the best approach. Humans work at these companies too, and everyone is prone to mistakes,...(read more)

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  • Generating Landed Cost Management Charges using Custom Pricing Attributes

    - by ChristineS-Oracle
    Learn how to incorporate Custom Pricing Attributes into Landed Cost Management through a new whitepaper.  The new application, Landed Cost Management (LCM), enables exact shipment charges to be applied to incoming receipts. These charges are calculated using the Freight and Special Charges functionality from Advanced Pricing within the Pricing Transaction Entity of “Purchasing”.Advanced Pricing is very flexible in that custom attributes can be defined to derive specific charges. The way that Landed Cost Management builds these attributes is different from the processing for Advanced Pricing with Purchasing.The whitepaper can be downloaded from document Oracle Advanced Pricing White Papers, Doc ID 136687.1.

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  • Function that requires many parameters

    - by user877329
    I have a problem related to this: Are there guidelines on how many parameters a function should accept? In my case, I have a function that describes a rounded rectangle. The caller specifies An integer which determines how the rectangle should be merged into previously created shapes An Anchor, which is a point that is used for alignment (right, left, top, bottom etc). (0,-1) means that position (next parameter) describes the top, middle point of the rectangle. The position of the rectangle Width and height Corner radius Should I use Parameter Object pattern in this case? It is hard to see how these parameters are related

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  • Where to install bootloader when installing Ubuntu as secondary OS?

    - by HelpNeeder
    I'm trying to install Ubuntu as secondary OS on my laptop. I have Windows 8 already installed on my laptop. Now, I know how to run Ubuntu from USB drive, I created addition partition and formatted it to EXT4. So I'm ready to install. Now, 'Device for boot loader installation:' displays: /dev/sta ATA HITACHI (750 GB) /dev/sta1 Windows 8 (loader) /dev/sta2 /dev/sta5 /dev/sta6 Ubuntu 12.04 (12.04) /dev/stb I tries choosing Ubuntu 12.04 partition but it doesn't even let me to pick which OS to install and goes straight to Windows 8. Which partition I must choose to be able to pick which OS to boot from? Preferably, set up so Windows 8 will be at first place, and Ubuntu on second. Any ideas? I don't want to mess up anything if I pick something wrong.

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  • What is the concept behind writing a cancel operation in c++?

    - by ToMan
    I'm attempting to write a cancel operation for a software download application. This application will first transfer the software to the device and then install the software on it. (These are givens I'm not allowed to change). What should the cancel operation do? When a user presses 'cancel', the application should stop transferring/installing the software immediately. Question: Since I've never written a "cancel" function, I'm wondering what are the types of things to consider when writing the code, and what are the common bugs I should expect and how to deal with them? Couldn't find anything in google so if you have some links that would be good reads I'd really appreciate it since I'm not looking for answers I'm just looking for guidelines/macro/concept help

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  • Writing a program in C++ and I need help [migrated]

    - by compscinoob
    So I am a new to this. I am trying to write a program with a function double_product(vector< double a, vector< double b) that computes the scalar product of two vectors. The scalar product is $a_{0}b_{0}+a_{1}b_{1}+...a_{n-1}b_{n-1}$. Here is what I have. It is a mess, but I am trying! #include<iostream> #include<vector> using namespace std; class Scalar_product { public: Scalar_product(vector<double> a, vector<bouble> b); }; double scalar_product(vector<double> a, vector<double> b) { double product = 0; for (int i=0; i <=a.size()-1; i++) for (int i=0; i <=b.size()-1; i++) product = product + (a[i])*(b[i]); return product; } int main() { cout << product << endl; return 0; }

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  • Writing a method to 'transform' an immutable object: how should I approach this?

    - by Prog
    (While this question has to do with a concrete coding dilemma, it's mostly about what's the best way to design a function.) I'm writing a method that should take two Color objects, and gradually transform the first Color into the second one, creating an animation. The method will be in a utility class. My problem is that Color is an immutable object. That means that I can't do color.setRGB or color.setBlue inside a loop in the method. What I can do, is instantiate a new Color and return it from the method. But then I won't be able to gradually change the color. So I thought of three possible solutions: 1- The client code includes the method call inside a loop. For example: int duration = 1500; // duration of the animation in milliseconds int steps = 20; // how many 'cycles' the animation will take for(int i=0; i<steps; i++) color = transformColor(color, targetColor, duration, steps); And the method would look like this: Color transformColor(Color original, Color target, int duration, int steps){ int redDiff = target.getRed() - original.getRed(); int redAddition = redDiff / steps; int newRed = original.getRed() + redAddition; // same for green and blue .. Thread.sleep(duration / STEPS); // exception handling omitted return new Color(newRed, newGreen, newBlue); } The disadvantage of this approach is that the client code has to "do part of the method's job" and include a for loop. The method doesn't do it's work entirely on it's own, which I don't like. 2- Make a mutable Color subclass with methods such as setRed, and pass objects of this class into transformColor. Then it could look something like this: void transformColor(MutableColor original, Color target, int duration){ final int STEPS = 20; int redDiff = target.getRed() - original.getRed(); int redAddition = redDiff / steps; int newRed = original.getRed() + redAddition; // same for green and blue .. for(int i=0; i<STEPS; i++){ original.setRed(original.getRed() + redAddition); // same for green and blue .. Thread.sleep(duration / STEPS); // exception handling omitted } } Then the calling code would usually look something like this: // The method will usually transform colors of JComponents JComponent someComponent = ... ; // setting the Color in JComponent to be a MutableColor Color mutableColor = new MutableColor(someComponent.getForeground()); someComponent.setForeground(mutableColor); // later, transforming the Color in the JComponent transformColor((MutableColor)someComponent.getForeground(), new Color(200,100,150), 2000); The disadvantage is - the need to create a new class MutableColor, and also the need to do casting. 3- Pass into the method the actual mutable object that holds the color. Then the method could do object.setColor or similar every iteration of the loop. Two disadvantages: A- Not so elegant. Passing in the object that holds the color just to transform the color feels unnatural. B- While most of the time this method will be used to transform colors inside JComponent objects, other kinds of objects may have colors too. So the method would need to be overloaded to receive other types, or receive Objects and have instanceof checks inside.. Not optimal. Right now I think I like solution #2 the most, than solution #1 and solution #3 the least. However I'd like to hear your opinions and suggestions regarding this.

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  • Extra fulltext ordering criteria beyond default relevance

    - by Jeremy Warne
    I'm implementing an ingredient text search, for adding ingredients to a recipe. I've currently got a full text index on the ingredient name, which is stored in a single text field, like so: "Sauce, tomato, lite, Heinz" I've found that because there are a lot of ingredients with very similar names in the database, simply sorting by relevance doesn't work that well a lot of the time. So, I've found myself sorting by a bunch of my own rules of thumb, which probably duplicates a lot of the full-text search algorithm which spits out a numerical relevance. For instance (abridged): ORDER BY [ingredient name is exactly search term], [ingredient name starts with search term], [ingredient name starts with any word from the search and contains all search terms in some order], [ingredient name contains all search terms in some order], ...and so on. Each of these is defined in the SELECT specification as an expression returning either 1 or 0, and so I order by those in sequential order. I would love to hear suggestions for: A better way to define complicated order-by criteria in one place, say perhaps in a view or stored procedure that you can pass just the search term to and get back a set of results without having to worry about how they're ordered? A better tool for this than MySQL's fulltext engine -- perhaps if I was using Sphinx or something [which I've heard of but not used before], would I find some sort of complicated config option designed to solve problems like this? Some google search terms which might turn up discussion on how to order text items within a specific domain like this? I haven't found much that's of use. Thanks for reading!

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  • What is the purpose of a boot priority sequence or order in BIOS

    - by rbeede
    A BIOS provides multiple options for specifying an order/priority to search for boot devices. Is there really much of a purpose now to have to specify more than one possible boot device? It would seem to me it is only useful when popping in an CD/DVD to install an OS after which the common scenario is to always boot from the hard drive unless something is broken. I'm curious as to why not simply have 1 option/device to set in the BIOS and expect the user to press a key to do alternate boot instead? Is there still a scenario for having the BIOS try multiple devices in a configured order?

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  • Excel: Plot order total in map coordinates

    - by Phliplip
    I have a set of data that looks like this: -X--Y----Amount- AE 24 $178,00 Y 27 $162,00 AD 34 $680,00 AK 35 $178,00 Y 25 $29,00 U 23 $178,00 X 38 $193,00 AC 30 $226,00 AK 39 $152,00 AJ 34 $217,00 AC 35 $183,00 AA 22 $211,00 Z 19 $172,00 AJ 32 $187,00 AF 26 $272,00 AI 27 $220,00 AJ 34 $320,00 AB 32 $183,00 AB 35 $272,00 AC 32 $207,00 AB 28 $178,00 AC 30 $168,00 AC 28 $178,00 AB 32 $310,00 AD 30 $188,00 AB 35 $188,00 The sample above is only an excerpt of the total dataset of 16K rows Each row represents a single delivery order, where the 2 first columns are the map coordinate and the third the purchase amount. Would it be possible to plot the above data in a chart or coordinate system. Where the each plot should be a summary of all sales in the same map coordinate. Also a similar chart of order count would be nice to have.

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  • What's up with tab order on my Mac?

    - by biged781
    So, I just got my first Mac. It is slick, and I feel like I don't know how to do anything, but overall it is a great machine. However, I am becoming frustrated with the tab order in most web pages. For example, this site. If I am composing a comment and press tab, focus is set to the address bar. I would like the focus to shift to the button next to the text area, but no luck. Also, I cannot seem to tab into combo boxes in form pages. What is going on here exactly? This happens in FireFox as well as Safari. I don't get why the tab order of a page would not be respected. Any help is appreciated.

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  • Eclipse Juno Switch Editor in Order

    - by inspectorG4dget
    In case it matters: OS: Mac OS X Lion (10.7.4) Eclipse: Juno, Build id: 20120614-1722 I have several files open in my eclipse workspace as tabs. The default shortcuts for previous and next editors are ?F6 and ?shiftF6. I know how to change these shortcuts, that's not the issue. However, what I want to do, is switch between editors in the way in which they're ordered in the tab bar. Currently, the editors change in order of last used/viewed. So, if I had three files (A, B and C in order) open and I'm currently editing A and I edited B last, when I use the shortcut for "Previous Editor", it takes me to B instead of C (and vice versa). Is there any way for me to get this functionality out of eclipse (if so, how)? Thank you

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