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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.

Comments

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

what is variations in raman spectra for nanomaterials
Jyoti Reply
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
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
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
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
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.
Bharti
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
Daniel
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit 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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