Skip to main content

Packages in ADA

Benefits of Packages
  1. Packages can be compiled, debugged independently
  2. software maintenance is very easier
  3. Once package is developed, they can be made accessible to everyone who has access to it.
  4. packages provide more security                                                                                                            
Packages contains two parts 1) a specification and 2) a body
Specification interfaces to the outside world.
body contains the executable statements associated with the functions

Examples of packages includ, COMPLEX NUMBERS Calculations, Creation of TIMER and CLOCK using packages and made as a library

Example
//Package specification describes the functions and variables relevant to complex number and their addition and subtraction operations

package COMPLEX_NUMBER is
type COMPLEX is 
record
 real, imag:float;
end record;
function ADD(a,b:COMPLEX) return COMPLEX;
function SUB(a,b:COMPLEX) return COMPLEX;
end COMPLEX_NUMBER;

//Paackage body will implement the function specified in the package specification

package body  COMPLEX_NUMBER is
with ROOTS; //ROOTS is also a package and now used as alibrary
use ROOTS;
with TRIGONO;
use TRIGONO;

begin 
function ADD(a,b:COMPLEX) return COMPLEX is 
return((a.real+b.real,a.imag+b.imag));
end ADD;
function SUB(a,b:COMPLEX) return COMPLEX is 
return((a.real-b.real,a.imag-b.imag));
end SUB;

end COMPLEX_NUMBER;

//Package COMPLEX_NUMBER made available as a library

with COMPLEX_NUMBER;  //retrieve the COMPLEX_NUMBER package
package CMPLXUSE is 
use COMPLEX_NUMBER; //make package available to the procedure
a:COMPLEX:=(2,3);
b:COMPLEX:=(2,3);
c:COMPLEX;
begin 
c:=ADD(a,b);
c:=SUB(a,b);
end CMPLXUSE;


Comments

Popular posts from this blog

Installing TexLive 2019 in Ubuntu 18.04

Installation of TexLive 2019 in Linux (Ubuntu 18.04 LTS)
TeX (Tech)

Installation of TexLive 2019

Please watch the video for full installation



I used .iso file to download, the Total size is 3.3GB for Linux,

and i used the torrent file to download, it took me just 20 min to download the entire .iso file

Extract the .iso file to a folder and open a terminal

$] sudo ./install-tl
(it goes into a terminal mode, which is faster compared to the GUI Mode)

$] sudo ./install-tl -gui
after the installation, set the PATH, MANPATH and INFOPATH as suggested by LATEX

export PATH=$PATH:/usr/local/texlive/2019/bin/x86_64-linux
export MANPATH=/usr/local/texlive/2019/texmf-dist/doc/man
export INFOPATH=/usr/local/texlive/2019/texmf-dist/doc/info

put these lines in to the /home/pradeepkumar/.bashrc

$] gedit /home/pradeepkumar/.bashrc
We have installed TexLive 2019 and texstudio.

To install texstudio

$] sudo apt install texstudio
The look and feel of TexStudio looks like this image.


texlive, it install everyt…

Implementing a new system call in Kernel version 2.6.32

A system call is used by application or user programs to request service from the operating systems. Since the user programs does not have direct access to the kernel whereas the OS has the direct access. OS can access the hardware through system calls only.The following files has to be modified for implementing a system call/usr/src/linux-2.6.32.5/arch/x86/kernel/syscall_table_32.S/usr/src/linux-2.6.32.5/arch/x86/include/asm/unistd_32.h/usr/src/linux-2.6.32.5/include/linux/syscalls.h/usr/src/linux-2.6.32.5/MakefileNew set of files to be createdCreate a new directory newcall/ inside the path “/usr/src/linux-2.6.32.5/” Create new files Makefile, newcall.c and put them in the /usr/src/linux-2.6.32.5/newcall/ folder Create new user files (in any folder of Linux) to test the system call
testnewcall.c, testnewcall.h (created in /home/pradeepkumar) syscall_table_32.S Find the file /usr/src/linux-2.6.32.5/arch/x86/kernel/syscall_table_32.S and add the following line at the end
"…

Electrical Machine Design (equations)

FactorsDC Machine Transformers Induction Machines Synchronous MachinesOutput EquationPa=CoD2Ln, where Pa=P/h for generators, Pa=P for motorsFor Single Phase
Q=2.22 f Bm Ai Kw Aw d10-3
For Three Phase
Q=3.33 f Bm Ai Kw Aw d 10-3Q=CoD2 L ns
KVA Input Q=
HP * 0.746 / Cos f * hQ=CoD2 L ns
KVA Input Q=
HP * 0.746 / Cos f * h
For Turbo alternators
Q=1.11Bavac KwsVa2 L 10-3/nsOutput CoefficientCo=Bav ac* 10-3where Bav-magnetic loading and ac - electric loadingDNACo=11 Kws Bav ac 10-3Co=11 Kws Bav ac 10-3 Choice of Magnetic LoadingFlux Density in Teeth Frequency of Flux Reversals Size of machineDNAMagnetizing current, Flux Density, Iron lossIron loss, Stability, Voltage Rating, Parallel Operation, Transient ShortCircuit current Choice of Electric LoadingTemperature rise,
speed of machine, Voltage, Armature reaction, CommutationDNAOverload Capacity, Copper losses, Temperature rise, Leakage ReactanceCopper loss, Synchronous reactance, Temperature rise, Stray Load losses,
Voltage rating Flux …