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This is the key that causes the cursor to go down to the next line and return to the left side of the editing window.

For example, when creating the text shown in Figure 1 using a text editor on my Windows computer, I pressed the Enter key immediately following the -->for each line. This produced a newline in each case.

Figure 1 . Two physical lines.
I will end the line here -->and end the next line here -->

A logical line

A logical line may be the same as a physical line , or line joining rules (described later) can be used to construct a logical line from two or more physical lines.

Statements and logical lines

A statement cannot cross logical line boundaries except where the syntax allows for the newline character, such as in compound statements . I will show you an example of a compound statement later in this module.


We learned about comments in an earlier module. To summarize, a comment starts with a hash character (#) that is not part of a string literal (we also learned about string literals in an earlier module) . The comment ends at the end of the physical line.

Explicit line joining

You can join two or more physical lines to produce a logical line , using the backslash character as shown in Listing 1 .

Listing 1 . Explicit line joining.
a = 3 b = 4# construct c=a+b c \= \ a \+ \ bprint(c) # the output is 7

The backslash character

When a physical line ends in a backslash that is not part of a string literal or comment, that line is joined with the following physical line forming a single logical line .

The backslash and the following end-of-line character(s) are ignored by the interpreter and do not become part of the logical line.

In Listing 1 , the expression c=a+b is created by joining five consecutive physical lines to create one logical line .

For illustration only

Obviously, this is not how you would want to write a long script, but it is not unusual to break long expressions into two or more physical lines to makethem fit onto a prescribed page width.

No spaces or comments allowed

You must make certain that no space characters follow the backslash.

You may not place a comment following the backslash, and a backslash does not continue a comment.

Otherwise illegal

A backslash is illegal elsewhere on a line except inside a string literal.

Implicit line joining

Expressions in parentheses, square brackets, or curly brackets can be split over more than one physical line without using backslashes as shown in Listing 2 .

Listing 2 . Implicit line joining.
a = 3 b = 4c = (a # continue on next line + b)print(c) # the output is 7

You can also place a comment on a line that is being continued implicitly as shown in the third line of Listing 2 .

Also, you can indent the continuation line however you want. This is very useful for making the code more readable.

Blank lines

Lines containing only spaces, tabs, form feeds, and comments are ignored in scripts, but the behavior may be different in interactive mode, depending on theimplementation.

An example of some spaces and blank lines is shown in Listing 3 .

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
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Source:  OpenStax, Itse 1359 introduction to scripting languages: python. OpenStax CNX. Jan 22, 2016 Download for free at https://legacy.cnx.org/content/col11713/1.32
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