August 10, 2014

Write a python program for creating virtual file system on Linux environment.

1 comment:

# Developer: Manish Raj (technoslab@gmail.com)
import shelve, time, sys

class File(object):

    def __init__(self, name, type, parent=None, text=''):
        self.list = []
        self.name = name
        self.type = type
        self.time = int(time.time())
        self.parent = parent
        self.text = text

    def is_file(self, name):
        for node in self.list:
            if node.name == name:
                return True
        return False

    def is_dir(self, name):
        if(self.is_file(name)) and self.get(name).type == 'dir':
            return True
        return False

    def get(self, name):
        for node in self.list:
            if node.name == name:
                return node
        
    def add(self, name, type, text=''):
        self.list.append(File(name, type, self, text))
             
    def remove(self, name):
        self.list.remove(self.get(name))
            
    def rename(self, name):
        self.name = name

    def copy(self, src, dest):
        src = self.get(src)
        self.add(dest, src.type, src.text)

    def stat(self):
        print 'Listing', self.name
        for node in self.list:
            print 'Name:', node.name, '; Created:', node.time, '; Type:', node.type
            
    def read(self):
        print 'Reading file:', self.name
        print self.text

class FileSystem(object):
    
    COMMANDS = ['ls', 'mkdir', 'chdir', 'cd', 'rmdir', 'create', 'read', 'rm', 'mv', 'cp', 'help', 'exit']
    
    def __init__(self):
        self.io = shelve.open('file.sys', writeback=True)
        if self.io.has_key('fs'):
            self.root = self.io['fs']
        else:
            self.root = File('/', 'dir')
        self.curr = self.root

    def mkdir(self, cmd):
        if len(cmd) < 2 or cmd[1] == '':
            print 'mkdir - make directory'
            print 'usage: mkdir <dir_name>'
        else:
            name = cmd[1]
            if self.curr.is_file(name) == False:
                self.curr.add(name, 'dir')
            else:
                print name, ' - already exists.';

    def chdir(self, cmd):
        if len(cmd) < 2 or cmd[1] == '':
            print 'chdir - change directory.'
            print 'usage: chdir <dir_name>'
        else:
            name = cmd[1]
            if name == '..':
                if self.curr.parent is not None:
                    self.curr = self.curr.parent
            elif self.curr.is_dir(name):
                self.curr = self.curr.get(name)
            else:
                print name, ' - invalid directory.'

    def rmdir(self, cmd):
        if len(cmd) < 2 or cmd[1] == '':
            print 'rmdir - remove directory'
            print 'usage: rmdir <dir_name>'
        else:
            name = cmd[1]
            if self.curr.is_dir(name):
                self.curr.remove(name)
                print 'Directory deleted.'
            else:
                print name, ' - invalid directory.'
                
    
    def rm(self, cmd):
        if len(cmd) < 2 or cmd[1] == '':
            print 'rm - remove file'
            print 'usage: rm <file_name>'
        else:
            name = cmd[1]
            if self.curr.is_file(name) and not self.curr.is_dir(name):
                self.curr.remove(name)
                print 'File deleted.'
            else:
                print name, ' - invalid file.'

    def ls(self, cmd):
        if(len(cmd) > 1):
            print 'ls - list stats'
            print 'usage: ls'
        self.curr.stat()

    def create(self, cmd):
        if len(cmd) < 2 or cmd[1] == '':
            print 'create - create a file'
            print 'usage: create <file_name>'
        else:
            name = cmd[1]
            self.curr.add(name, 'file', raw_input('Enter file context: '))
            
    def read(self, cmd):
        if len(cmd) < 2 or cmd[1] == '':
            print 'read - read a file'
            print 'usage: read <file_name>'
        else:
            name = cmd[1]
            if self.curr.is_file(name):
                self.curr.get(name).read()
            else:
                print name, 'invalid file'

    def mv(self, cmd):
        if len(cmd) < 3 or cmd[1] == '':
            print 'mv - rename a file'
            print 'usage: mv <old_name> <new_name>'
        else:
            old_name = cmd[1]
            new_name = cmd[2]
            if self.curr.is_file(old_name):
                self.curr.get(old_name).rename(new_name)
            else:
                print old_name, 'invalid file'

    def cp(self, cmd):
        if len(cmd) < 3 or cmd[1] == '':
            print 'cp - copy a file'
            print 'usage: cp <src> <dest>'
        else:
            src = cmd[1]
            dest = cmd[2]
            if self.curr.is_file(src):
                self.curr.copy(src, dest)
            else:
                print src, 'invalid file'
    
    def save(self):
        self.io['fs'] = self.root
        self.io.sync()
            
    def help(self, cmd):
        print 'COMMANDS: mkdir, ls, chdir, rmdir, create, read, mv, cp, rm, exit'

    def exit(self, cmd):
        sys.exit(0)

def main():
    fs = FileSystem()
    while True:
        cmd = raw_input('> ').split(' ');
        method = None
        try:
            method = getattr(fs, cmd[0])
        except AttributeError:
            print 'Invalid command. Type "help".'
        if method is not None and cmd[0] in FileSystem.COMMANDS and callable(method):
            method(cmd)
            fs.save()
        else:
            print 'Invalid command. Type "help".'
main()
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August 07, 2014

Capture/Record webcam, desktop and audio under Ubuntu 14.04

1 comment:


Bash script:

fname=`date +"%d.%m.%Y_%H:%M:%S_%P"`.'_screencast.mp4'
vlc --qt-minimal-view v4l2:///dev/video0 &
vlc --qt-minimal-view screen:// :screen-fps=20 :screen-follow-mouse :live-caching=300 :input-slave=alsa://hw:0,0 :sout="#transcode{vcodec=h264,vb=384,fps=5,acodec=mpga}:duplicate{dst=std{mux=mp4,access=file,dst='$fname'}}" &

These set of commands start two instances of VLC.
The first command fires up a minimal view of VLC with video source "/dev/video0" (the default location of webcamera in most general cases).

The second command starts another minimal VLC instance with video from screen:// (desktop) and audio from default built-in microphone "hw:0,0". Output is encoded and saved in current directory as an mp4 file.

Recording stops when you close VLC instances.
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February 09, 2014

OOMP Assignment#4

No comments:
/*
Aim: Design a C++ Class "Complex" with data members for real and imaginary part. Provide
default and parametrized constructors. Write a program to perform arithmetic operations
of two complex numbers using operator overloading (using either member functions or
friend functions).
*/

#include <iostream>
#include <math.h>
using namespace std;

class Complex{
 public:
   int a;
   int b;
   Complex(){
     Complex(0, 0);
   }
   Complex(int x, int y){
     a = x;
     b = y;
   }
   void get(){
     cout << endl << "Enter real part: ";
     cin >> a;
     cout << endl << "Enter imaginary part: ";
     cin >> b;
     print();
   }
   void print(){
     cout << endl << a << " " << (b >= 0 ? "+" : "-") << " " << abs(b) << "i";
   }
   Complex operator + (Complex c){
     return Complex(a + c.a, b + c.b);
   }
   Complex operator - (Complex c){
     return Complex(a - c.a, b - c.b);
   }
   Complex operator *(Complex c){
     return Complex(a * c.a - b * c.b, a*c.b + c.a * b);
   }
   Complex operator /(Complex c){
     return Complex((a * c.a + b * c.b)/(c.a * c.a + c.b * c.b), (b * c.a - a * c.b)/(c.a * c.a + c.b * c.b));
   }
};

int main(){
 int choice;
 Complex c1, c2, c3;
 do{
   cout << endl << "-- Complex Numbers --";
   cout << endl << "1. Input numbers";
   cout << endl << "2. Display numbers";
   cout << endl << "3. Add";
   cout << endl << "4. Subtract";
   cout << endl << "5. Multiply";
   cout << endl << "6. Divide";
   cout << endl << "7. Exit";
   cout << endl << "Enter your choice: ";
   cin >> choice;
   switch(choice){
     case 1 : c1.get(); c2.get(); break;
     case 2 : c1.print(); c2.print(); break;
     case 3 :
       c3 = c1 + c2;
       cout << endl << "Result of addition: ";
       c3.print();
       break;
     case 4 :
       c3 = c1 - c2;
       cout << endl << "Result of subtraction: ";
       c3.print();
       break;
     case 5 :
       c3 = c1 * c2;
       cout << endl << "Result of multiplication: ";
       c3.print();
       break;
     case 6 :
       c3 = c1 / c2;
       cout << endl << "Result of division: ";
       c3.print();
       break;
     default : cout << endl << "Invalid choice!"; break;
   }
 }while(choice != 7);
 return 0;
}

/*
---------------------------------------
             OUTPUT
---------------------------------------

-- Complex Numbers --
1. Input numbers
2. Display numbers
3. Add
4. Subtract
5. Multiply
6. Divide
7. Exit
Enter your choice: 1

Enter real part: 10

Enter imaginary part: 20

10 + 20i
Enter real part: -15

Enter imaginary part: -25

-15 - 25i
-- Complex Numbers --
1. Input numbers
2. Display numbers
3. Add
4. Subtract
5. Multiply
6. Divide
7. Exit
Enter your choice: 2

10 + 20i
-15 - 25i
-- Complex Numbers --
1. Input numbers
2. Display numbers
3. Add
4. Subtract
5. Multiply
6. Divide
7. Exit
Enter your choice: 3

Result of addition:
-5 - 5i
-- Complex Numbers --
1. Input numbers
2. Display numbers
3. Add
4. Subtract
5. Multiply
6. Divide
7. Exit
Enter your choice: 4

Result of subtraction:
25 + 45i
-- Complex Numbers --
1. Input numbers
2. Display numbers
3. Add
4. Subtract
5. Multiply
6. Divide
7. Exit
Enter your choice: 5

Result of multiplication:
350 - 550i
-- Complex Numbers --
1. Input numbers
2. Display numbers
3. Add
4. Subtract
5. Multiply
6. Divide
7. Exit
Enter your choice: 6

Result of division:
0 + 0i
-- Complex Numbers --
1. Input numbers
2. Display numbers
3. Add
4. Subtract
5. Multiply
6. Divide
7. Exit
Enter your choice: 7
*/
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OOMP Assignment#3

1 comment:
/*
Aim: Develop an object oriented program in C++ to create a database of the personnel
information system containing the following information: Name, Date of Birth, Blood
group, Height, Weight, Insurance Policy, number, Contact address, telephone number,
driving license no. etc Construct the database with suitable member functions for
initializing and destroying the data viz constructor, default constructor, copy, constructor,
destructor, static member functions, friend class, this pointer, inline code and dynamic
memory allocation operators-new and delete.
*/

#include <iostream>
#define MAX_RECORDS 50
using namespace std;

class Information{
 friend class Records;
 private:
   string name, dateOfBirth, bloodGroup, contactAddress;
   float height, weight;
   double policyNumber, telephoneNumber, licenseNumber;
 public:
   Information(string n, string dob, string bg, string ca, int h, int w, double pn, double tn, double ln){
     this->name = string(n);
     this->dateOfBirth = string(dob);
     this->bloodGroup = string(bg);
     this->contactAddress = string(ca);
     this->height = h;
     this->weight = w;
     this->policyNumber = pn;
     this->telephoneNumber = tn;
     this->licenseNumber = ln;
   }
   Information(){
     Information("", "", "", "", 0, 0, 0, 0, 0);
   }
   Information(const Information& otherInfo){
     this->name = otherInfo.name;
     this->dateOfBirth = otherInfo.dateOfBirth;
     this->bloodGroup = otherInfo.bloodGroup;
     this->contactAddress = otherInfo.contactAddress;
     this->height = otherInfo.height;
     this->weight = otherInfo.weight;
     this->policyNumber = otherInfo.policyNumber;
     this->telephoneNumber = otherInfo.telephoneNumber;
     this->licenseNumber = otherInfo.licenseNumber;
   }
   inline void acceptValues(){
     cout << endl << "Enter personal details: ";
     cout << endl << "Name: ";
     cin >> this->name;
     cout << endl << "Date Of Birth: ";
     cin >> this->dateOfBirth;
     cout << endl << "Blood Group: ";
     cin >> this->bloodGroup;
     cout << endl << "Contact Address: ";
     cin >> this->contactAddress;
     cout << endl << "Height: ";
     cin >> this->height;
     cout << endl << "Weight: ";
     cin >> this->weight;
     cout << endl << "Policy Number: ";
     cin >> this->policyNumber;
     cout << endl << "Telephone Number: ";
     cin >> this->telephoneNumber;
     cout << endl << "License Number: ";
     cin >> this->licenseNumber;
   }
   inline void display(){
     cout << endl << "Personal details: " << endl;
     cout << endl << "Name: " << this->name;
     cout << endl << "Date Of Birth: " << this->dateOfBirth;
     cout << endl << "Blood Group: " << this->bloodGroup;
     cout << endl << "Contact Address: " << this->contactAddress;
     cout << endl << "Height: " << this->height;
     cout << endl << "Weight: " << this->weight;
     cout << endl << "Policy Number: " << this->policyNumber;
     cout << endl << "Telephone Number: " << this->telephoneNumber;
     cout << endl << "License Number: " << this->licenseNumber << endl;
   }
};

class Records{
 private:
   Information * records[MAX_RECORDS];
 public:
   static int COUNT;
   static int getCount(){
     return COUNT;
   }
   static void incCount(){
     COUNT++;
   }
   void add(){
     records[Records::getCount()] = new Information();
     records[Records::getCount()]->acceptValues();
     Records::incCount();
   }
   void display(){
     for(int i = 0; i < Records::getCount(); i++){
       records[i]->display();
     }
   }
   ~Records(){
     for(int i = 0; i < Records::getCount(); i++){
       delete records[i];
     }
   }
};

int Records::COUNT = 0;

int main(){
 int choice;
 Records * rs = new Records();
 do{
   cout << endl << "-- Personal Information --";
   cout << endl << "1. Add information";
   cout << endl << "2. Display information";
   cout << endl << "3. Exit";
   cout << endl << "Your choice: ";
   cin >> choice;
   switch(choice){
     case 1 : rs->add(); break;
     case 2 : rs->display(); break;
   }
 }while(choice != 3);
 delete rs;
 return 0;
}

/*
---------------------------------------
             OUTPUT
---------------------------------------

-- Personal Information --
1. Add information
2. Display information
3. Exit
Your choice: 1

Enter personal details:
Name: Man

Date Of Birth: 4/4/1994

Blood Group: O+

Contact Address: Pune

Height: 160

Weight: 65

Policy Number: 7766554433

Telephone Number: 9988776655

License Number: 123456890

-- Personal Information --
1. Add information
2. Display information
3. Exit
Your choice: 1

Enter personal details:
Name: Tau

Date Of Birth: 5/5/1995

Blood Group: AB-

Contact Address: Mumbai

Height: 160

Weight: 45

Policy Number: 1234554321

Telephone Number: 9988006677

License Number: 0987654321

-- Personal Information --
1. Add information
2. Display information
3. Exit
Your choice: 2

Personal details:

Name: Man
Date Of Birth: 4/4/1994
Blood Group: O+
Contact Address: Pune
Height: 160
Weight: 65
Policy Number: 7.76655e+009
Telephone Number: 9.98878e+009
License Number: 1.23457e+008

Personal details:

Name: Tau
Date Of Birth: 5/5/1995
Blood Group: AB-
Contact Address: Mumbai
Height: 160
Weight: 45
Policy Number: 1.23455e+009
Telephone Number: 9.98801e+009
License Number: 9.87654e+008

-- Personal Information --
1. Add information
2. Display information
3. Exit
Your choice: 3
*/
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OOMP Assignment#2

No comments:
/*
Aim: A book shop maintains the inventory of books that are being sold at the shop. The list includes details such as author, title, price, publisher and stock position. Whenever a
customer wants a book, the sales person inputs the title and author and the system
searches the list and displays whether it is available or not. If it is not, an appropriate
message is displayed. If it is, then the system displays the book details and requests
for the number of copies required. If the requested copies book details and requests
for the number of copies required. If the requested copies are available, the total cost
of the requested copies is displayed; otherwise the message "Required copies not in
stock" is displayed. Design a system using a class called books with suitable member functions and
Constructors. Use new operator in constructors to allocate memory space required.
Implement C++ program for the system.
*/

#include <iostream>
#include <string.h>
#define MAX_BOOKS 50
using namespace std;

class Book{
 friend class BookShop;
   string author;
   string title;
   string publisher;
   int stockPosition;
   float price;
 public:
   Book(){
     author = "";
     title = "";
     publisher = "";
     stockPosition = 0;
     price = 0;
   }
   float getPrice(int numOrder){
     return price * numOrder;
   }
   bool isAvailable(int numOrder){
     return numOrder <= stockPosition;
   }
   void printDetails(){
     cout << endl << "--- Book details ---";
     cout << endl << "Title: " << title;
     cout << endl << "Author: " << author;
     cout << endl << "Publisher: " << publisher;
     cout << endl << "StockPosition: " << stockPosition;
     cout << endl << "Price: Rs." << price;
   }
   void get(){
     cout << endl << "Enter new book details: ";
     cout << endl << "Title: ";
     cin >> title;
     cout << endl << "Author: ";
     cin >> author;
     cout << endl << "Publisher: ";
     cin >> publisher;
     cout << endl << "Price: ";
     cin >> price;
     cout << endl << "Stock Position: ";
     cin >> stockPosition;
   }
   void placeOrder(){
     int numOrder;
     cout << endl << "Enter number of copies: ";
     cin >> numOrder;
     if(isAvailable(numOrder)){
       cout << endl << "Required copies are available in stock. Total price: Rs." << getPrice(numOrder);
     }else{
       cout << endl << "Required copies not in stock.";
     }
   }
};

class BookShop{
   Book * books[MAX_BOOKS];
   int index;
 public:
   BookShop(){
     index = 0;
   }
   void add(){
     books[index] = new Book();
     books[index]->get();
     index++;
   }
   void request(){
     int choice = 0, search = -1;
     cout << endl << "Search for book by: ";
     cout << endl << "1) Title";
     cout << endl << "2) Author";
     cout << endl << "Enter choice: ";
     cin >> choice;
     switch(choice){
       case 1 : search = searchTitle(); break;
       case 2 : search = searchAuthor(); break;
       default: cout << endl << "Invalid choice!"; break;
     }
     if(search == -1){
       cout << endl << "No results found!";
     }else{
       cout << endl << "Book found: ";
       books[search]->printDetails();
       books[search]->placeOrder();
     }
   }
   int searchTitle(){
     string title;
     cout << endl << "Enter book title to search: ";
     cin >> title;
     for(int i = 0; i < index; i++){
       if(title.compare(books[i]->title) == 0){
         return i;
       }
     }
     return -1;
   }
   int searchAuthor(){
     string author;
     cout << endl << "Enter author name to search: ";
     cin >> author;
     for(int i = 0; i < index; i++){
       if(author.compare(books[i]->author) == 0){
         return i;
       }
     }
     return -1;
   }
};


int main(){
 int choice;
 BookShop * bs = new BookShop();
 do{
   cout << endl << "-- Book Shop --";
   cout << endl << "1. Add book";
   cout << endl << "2. Request book";
   cout << endl << "3. Exit";
   cout << endl << "Your choice: ";
   cin >> choice;
   switch(choice){
     case 1 : bs->add(); break;
     case 2 : bs->request(); break;
   }
 }while(choice != 3);
 delete bs;
 return 0;
}

/*
---------------------------------------
             OUTPUT
---------------------------------------

-- Book Shop --
1. Add book
2. Request book
3. Exit
Your choice: 1

Enter new book details:
Title: Gravity

Author: Rohit

Publisher: GHRCEM

Price: 400

Stock Position: 10

-- Book Shop --
1. Add book
2. Request book
3. Exit
Your choice: 1

Enter new book details:
Title: Inferno

Author: Tauseef

Publisher: GHRCEM

Price: 350

Stock Position: 5

-- Book Shop --
1. Add book
2. Request book
3. Exit
Your choice: 2

Search for book by:
1) Title
2) Author
Enter choice: 1

Enter book title to search: Gravity

Book found:
--- Book details ---
Title: Gravity
Author: Rohit
Publisher: GHRCEM
StockPosition: 10
Price: Rs.400
Enter number of copies: 15

Required copies not in stock.
-- Book Shop --
1. Add book
2. Request book
3. Exit
Your choice: 2

Search for book by:
1) Title
2) Author
Enter choice: 2

Enter author name to search: Tauseef

Book found:
--- Book details ---
Title: Inferno
Author: Tauseef
Publisher: GHRCEM
StockPosition: 5
Price: Rs.350
Enter number of copies: 4

Required copies are available in stock. Total price: Rs.1400
-- Book Shop --
1. Add book
2. Request book
3. Exit
Your choice: 3
*/
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