Types and declarations, Python Programming

Assignment Help:

 

Java programs are  what  is known as statically and  strongly defined.  Thus,  the  kinds  of all the variables must  be known at the time that the program is written. That seems  that variables have to be declared to have  a particular type  before  they  are given.   It also seems  that  the  variables cannot  be used  in a way that is inconsistent with their kind.  So, for that point, you would define  x to be an integer by saying

 

int x;

x  = 6 * 7;

But you would get into trouble if you left out the definition, or did

int x;

x  = "thing";

 

because  a type checker  is execute  on your  program to make  sure that you don't try to use a variable in a way that is inconsistent with its declaration.

In Python, however, things  are a lot more  reliable.   There  are no variable definition, and  the similar variable may be used  at different positions  in your  program to hold  data  objects of different kinds.  So, the following is ok, in Python:

 

if x == 1:

x = 89.3

else:

x = "thing"

 

The advantage of having type  declarations and  compile-time type  checking, in Java, is that  a compiler can create an executable version of your  program that  runs  very  rapidly,  because  it may be certain about  what  kind of data is stored in each and every variable, and it does not have to calculate it at execution time. An additional advantage is that several programming mistakes can be caught at compile time, rather than  waiting until  the program is being execute.  Java could complain even before your program started to run that it could not evaluate

 

3 + "hi"

 

Python could not complain until it was executing the program and got to that point.

The advantage of the Python approach is that programs are shorter and cleaner seeing,  and possibly simpler to write.  The flexibility is often useful:  In Python, it is simple to create a list or array with objects of different types  saved in it. In Java, it may be done,  but it is trickier.  The disadvantage of the Python function is that  programs tend  to be lighter.  Also, the rigor  of compile time checking  may replace bugs, especially in big programs.

 


Related Discussions:- Types and declarations

Programs and data , Programs and Data Object-oriented programming is a...

Programs and Data Object-oriented programming is a popular way  of managing programs, which  groups together data  with  the procedures that  works on them,  thus  facilitatin

Normalize a vector, Normalize a vector Let's imagine we want  to norma...

Normalize a vector Let's imagine we want  to normalize a vector  of three  variables;  that  is to compute a new  vector  of three values,  such that its size  is 1. Here is o

#title.display of vanderwaals isotherm, draw the variation of pressure with...

draw the variation of pressure with volume of a real gas at temperatures lower than its critical temperature.also draw its surface of discontinuity

program that receives as input from the user, Write an algorithm for a pro...

Write an algorithm for a program that receives, as input from the user, 2 string variables and 2 integer variables; then joins together and displays the combined strings; and final

Python programme comparing for and while loops, 1)    Write a python progra...

1)    Write a python programmecomparing for and while loops like the following. Math Times table For Loop: 2x1=2 2x2=4 ..... 2x12=24 While Loop: 3x1=3 3x

Algorithm, given number isprime number or not

given number isprime number or not

Matrix, What are squared matrices?

What are squared matrices?

Homework Assignment #4, Finally! After years of adding unimportant sports,...

Finally! After years of adding unimportant sports, the IOC has finally added Shoe Tying to the Olympics. And you’ve been selected to write the software to handle the judging of t

Hw, Suppose the cover price of a book is $24.95, but bookstores get a 40% ...

Suppose the cover price of a book is $24.95, but bookstores get a 40% discount. Shipping costs $3 for the first copy and 75 cents for each additional copy. What is the tota

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd