1. Text Copyright (c) 2017 by Dr. E. Horvath
Creating Python 3 Scripts, Declaring Variables, Arithmetic Operators, and Formatting
Text Copyright (c) 2017 by Dr. E. Horvath

2. Creating Python 3 Scripts
Menu → Programming → Python 3 (IDLE)
IDLE = Integrated Developers Environment
File → New File
Run → Run Module or press F5 to run
Text Copyright (c) 2017 by Dr. E. Horvath

3. Text Copyright (c) 2017 by Dr. E. Horvath
Declaring Variables
An assignment statement is sufficient to declare a variable. The type of the data is based on the values assigned to a variable.
count = 5
temperature = 98.6
name = “Your name”
print(“count “ + str(count))
print outputs a value in the shell
Text Copyright (c) 2017 by Dr. E. Horvath

4. Precedence ( ) Parentheses ** Exponentiation +x, -x Positive, Negative
* / %
Multiplication, Division, Remainder
+ -
Addition, Subtraction
<, <=, >, >=, !=, ==
Relational Operators
not x
Boolean NOT
and
Boolean AND or
Boolean OR

5. Text Copyright (c) 2017 by Dr. E. Horvath
Input data
count = input(“Enter the count”)
Prompt the user for input
count = int(count)
Convert to an integer
print(“count “ + str(count))
print outputs a value in the shell + concatenate strings
str(count) covert to a string for output
temperature= input(“Enter the temperature”)
temperature = float(temperature)
Convert to a floating point value
name = input(“Enter your name”)
print(“name = “ + name)
Text Copyright (c) 2017 by Dr. E. Horvath

6. Text Copyright (c) 2017 by Dr. E. Horvath
Escape Characters
print(“\”Your name \”\n”) \”
Print a double quote \n
New line character
Text Copyright (c) 2017 by Dr. E. Horvath

7. Text Copyright (c) 2017 by Dr. E. Horvath
round function
The round function rounds a floating point value to a specific number of decimal places.
h =
h1 = round(h,2)
h1 = 45.44
h2 = round(h,1)
h2 = 45.4
Text Copyright (c) 2017 by Dr. E. Horvath

8. Text Copyright (c) 2017 by Dr. E. Horvath
Formatting Output
pi =
name = “Your name”
msg = "pi: "+ format(pi,'7.2f')
7 spaces, 2 decimal places of precision
f indicates floating point
msg = "pi: "+ format(pi,'0.3e')
no additional spaces before the decimal point
3 decimal places of precision
e indicates exponential
Text Copyright (c) 2017 by Dr. E. Horvath

9. Text Copyright (c) 2017 by Dr. E. Horvath
Formatting Output
pi =
name = “Your name”
msg = "pi: "+ format(p,'10,.2f')
10 spaces, comma for thousand places, 2 decimal places of precisions
f indicates floating point
msg = "name: "+ format(name,'15s'')
15 spaces
s indicates string data
Text Copyright (c) 2017 by Dr. E. Horvath

10. Text Copyright (c) 2017 by Dr. E. Horvath
Formatting Output
pi =
hours = 24
msg = “pi {:7.2f} hours {:3d}".format(pi,hours)
7 spaces, 2 decimal places of precision
f indicates floating point
3 spaces for an integer data
Text Copyright (c) 2017 by Dr. E. Horvath

11. Text Copyright (c) 2017 by Dr. E. Horvath
Formatting Output
msg = "pi {0:7.2e} hours {1:04d}".format(pi,hours)
7 spaces before the decimal point
2 decimal places of precision
e indicates exponential
preceeding zero, 4 spaces for an integer
name = “Your name”
msg = Your name is {0:>15s}".format(name)
15 spaces
> indicates right align
s indicates string
Text Copyright (c) 2017 by Dr. E. Horvath