# 1.5 Itse1359-1030-variables and identifiers  (Page 3/7)

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## Numbers

Numbers can be any of the digit characters between and including 0 and 9.

## Style

Click PEP 8 -- Style Guide for Python Code to learn more about how to create identifiers for variables and other programming elements as well.

## Start the interactive Python environment

The first thing that you need to do is to start the interactive programming environment. If you have forgotten how to do that, see the module titled Itse1359-1010-Getting Started .

## Create and use some variables

The interactive fragment shown in Figure 1 :

• Creates two variables named x and y,
• Populates them by assigning values of 6 and 5 to them respectively
• Adds their values together to produce the sum value of 11.
Figure 1 . Create and use some variables.
```>>>x=6 # create and populate x>>>y=5 # create and populate y>>>x+y # add x to y and display the sum 11>>>```

## Back to the pigeonholes

Using the informal jargon from an earlier paragraph, two pigeonholes are established in memory and are given nicknames of x and y.

## The assignment operator

Integer values of 6 and 5 are stored in the two pigeonholes using the assignment operator (=).

The use of the assignment operator in this fashion causes the value of its right operand to be stored in the pigeonhole identified by its left operand .

## What is an operand ?

If you don't recognize the use of the term operand, see the earlier module titled Itse1359-1020-Numbers for an explanation.

In this case, the right operands of the assignment operators are literal numeric values .

The left operands of the assignment operators are the nicknames identifying the two memory locations that constitute the variables named x and y.

The values are retrieved from eachpigeonhole and added together in the third line of code. The result of the addition (11) is displayed as output from the expression x+y .

## Assigning the same value to several variables

Python allows you to assign the same value to several variables, causing them to come into existence (begin to occupy memory) at the same time if necessary

Consider the interactive fragment shown in Figure 2 .

Figure 2 . Assigning the same value to several variables.
```>>>a=b=c=10 # assign 10 to several variables>>>a+b+c # add them together 30>>>a=b=c=20 # assign 20 to same variables>>>a+b+c # add them together 60>>>```

## Create three variables

The first line of code in Figure 2 creates three variables named a , b , and c , and assigns a value of 10 to each of them.

They are then added together, in the second line of code, to produce an output value of 30.

## Assign different values

The fourth line of code assigns the value of 20 to the same three variables, replacing what was previously there with the new value. Againthey are added together, this time producing an output value of 60.

## A more comprehensive explanation

Pigeonhole explanations are good for starters, but let's move on to a more comprehensive and technically correct explanation.

According to the Python gurus, everything (or at least almost everything) in Python is an object. I indicated earlier that data values are stored in variables.In reality, that is not the case. Figure 3 shows the truth about pigeonholes, variables, and objects.

what is math number
x-2y+3z=-3 2x-y+z=7 -x+3y-z=6
Need help solving this problem (2/7)^-2
x+2y-z=7
Sidiki
what is the coefficient of -4×
-1
Shedrak
the operation * is x * y =x + y/ 1+(x × y) show if the operation is commutative if x × y is not equal to -1
An investment account was opened with an initial deposit of \$9,600 and earns 7.4% interest, compounded continuously. How much will the account be worth after 15 years?
lim x to infinity e^1-e^-1/log(1+x)
given eccentricity and a point find the equiation
12, 17, 22.... 25th term
12, 17, 22.... 25th term
Akash
College algebra is really hard?
Absolutely, for me. My problems with math started in First grade...involving a nun Sister Anastasia, bad vision, talking & getting expelled from Catholic school. When it comes to math I just can't focus and all I can hear is our family silverware banging and clanging on the pink Formica table.
Carole
I'm 13 and I understand it great
AJ
I am 1 year old but I can do it! 1+1=2 proof very hard for me though.
Atone
hi
Not really they are just easy concepts which can be understood if you have great basics. I am 14 I understood them easily.
Vedant
hi vedant can u help me with some assignments
Solomon
find the 15th term of the geometric sequince whose first is 18 and last term of 387
I know this work
salma
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
hmm well what is the answer
Abhi
If f(x) = x-2 then, f(3) when 5f(x+1) 5((3-2)+1) 5(1+1) 5(2) 10
Augustine
how do they get the third part x = (32)5/4
make 5/4 into a mixed number, make that a decimal, and then multiply 32 by the decimal 5/4 turns out to be
AJ
how
Sheref
can someone help me with some logarithmic and exponential equations.
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
I don't understand what the A with approx sign and the boxed x mean
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
oops. ignore that.
so you not have an equal sign anywhere in the original equation?
hmm
Abhi
is it a question of log
Abhi
🤔.
Abhi
I rally confuse this number And equations too I need exactly help
salma
But this is not salma it's Faiza live in lousvile Ky I garbage this so I am going collage with JCTC that the of the collage thank you my friends
salma
Commplementary angles
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
hii
Uday
hi
salma
hi
Ayuba
Hello
opoku
hi
Ali
greetings from Iran
Ali
salut. from Algeria
Bach
hi
Nharnhar
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