<< Chapter < Page Chapter >> Page >

Introduction

A structure type can contain a number of dissimilar data objects within it. Unlike a simple variable (which contains only one data object) or an array (which, although it contains more than one data item, only contains items of a single data type),a structure is a collection of related data of different types. a name, for example, might be array of characters, an age might be integer. A structure representing a person, say, could contain both a name and an age, each represented in the appropriate format.

Declarations and usage of structures

Until now, all the data that we have dealt with has been either of a basic type such as char, int and double…, or an array of those types. However, there are many situations in real life where a data item needs to be made up from other more basic types. We could do this with an array if the constituent types were all the same, but often they are different. For example, suppose we want to record the details of each student in a class. The detail of each student might be as follow:

  • A unique student number, which could be represented as a string (an array of char ).
  • The student’s name, which could be represented as a string (an array of char ).
  • Final mark for the Introduction to computer science course, which is a floating point value (a float ).

Creating structures as new data types

The definition of a structure type begins with the keyword struct, and contains a list of declarations of the structure's members, in braces:

struct structTag {<list of members>; };
Definition ends with semicolon (;)

The three components above can be placed in a structure declared like this:

struct Student {char StudentID[10];char name[30];float markCS ; };
Got questions? Get instant answers now!

The keyword struct introduces a structure declaration, which is a list of declarations enclosed in braces. An optional name called a structure tag may follow the word struct (as with Student here). The tag names this kind of structure, and can be used subsequently as a shorthand for the part of the declaration in braces. The variables named in a structure are called members. A structure member or tag and an ordinary (i.e., non-member) variable can have the same name without conflict, since they can always be distinguished by context. Furthermore, the same member names may occur in different structures, although as a matter of style one would normally use the same names only for closely related objects.

Creating variable of a struct type

Structure types are not considered a variable declaration, just definition of a new type, so they cannot store anything until we declare variable of this type. Here is how we would create:

type_name_of_struct name_of_variable;

Creating three variables a, b, c of the Student type:

Student a, b, c;

Creating an array of the Student type:

Student studentCS[50];
Got questions? Get instant answers now!

A member of a structure may have any desired complete type, including previously defined structure types. They must not be variable-length arrays, or pointers to such arrays. For instance, now we want to record more information of students, for example their date of birth, which comprises the day, month and year. So first, let's start with the date, because that is a new type that we may be able to use in a variety of situations. We can declare a new type for a Date thus:

Questions & Answers

how can chip be made from sand
Eke Reply
is this allso about nanoscale material
Almas
are nano particles real
Missy Reply
yeah
Joseph
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
Lohitha
where is the latest information on a no technology how can I find it
William
currently
William
where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
has a lot of application modern world
Kamaluddeen
yes
narayan
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
Bhagvanji
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, Introduction to computer science. OpenStax CNX. Jul 29, 2009 Download for free at http://cnx.org/content/col10776/1.1
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Introduction to computer science' conversation and receive update notifications?

Ask