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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

so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
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
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
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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