Monday, August 25th, 2025

Getting started with Jupyter notebook

• We can execute a cell using SHIFT + ENTER.
• We can add a new cell using the plus symbol in the top-left corner. Alternatively, you can select a cell and hit A to add a cell above, or B to add a cell below.
• We can delete a cell by selecting hit, then hitting D, D.

2 + 7

9

100 + 7

107

Arithmetic operations

Addition:

400 + 3

403

Subtraction:

300 - 5

295

Multiplication:

50 * 3

150

Division:

10 / 2

5.0

Exponentiation:

2^5

7

To perform exponentiation, use ** or the pow function instead of ^:

2**5

32

pow(2,5)

32

Using the standard division / will return what is called a float.

5 / 2

2.5

6/3

2.0

5 / 3

1.6666666666666667

Integers vs floats

• integers = numbers without any decimal point
• floats = numbers with a decimal point
• operations on integers are exact
• operations on floats are approximate
• integers can be arbitrarily large, but floats are represented only within a finite range.

2.0 ** 100

1.2676506002282294e+30

2**100

1267650600228229401496703205376

2.0**1200

---------------------------------------------------------------------------
OverflowError                             Traceback (most recent call last)
Cell In[23], line 1
----> 1 2.0**1200

OverflowError: (34, 'Result too large')

2**1200

17218479456385750618067377696052635483579924745448689921733236816400740691241745619397484537236046173286370919031961587788584927290816661024991609882728717344659503471655990880884679896520055123906467064419056526231345685268240569209892573766037966584735183775739433978714578587782701380797240772477647874555986712746271362892227516205318914435913511141036261376

Markdown

Markdown is a markup language used for creating formatted text. In Jupyter, we create Markdown cells for this text.

This cell will throw an error.

  Cell In[27], line 1
    This cell will throw an error.
         ^
SyntaxError: invalid syntax

This cell will not throw an error.

We can create headings using hashtags, #:

This is a heading

This is a sub-heading

This is a sub-sub-heading

We can generate bulleted (un-numbered) using a space and hyphen:

Here is a list:

• Item 1
• This is item 2
• I'm item 3

We can also nest lists using additional spaces:

Here is a list with nested sub-lists:

• Item 1
• Item 2
  • Item 2(a)
  • Item 2(b)
  • Item 2(c)
• Item 3

We can also create numbered lists using 1., 2., etc. Note: A numbered list will always be enumerated 1, 2, 3... regardless of how you've actually numbered the items.

Here is a numbered list:

1. Item 1
2. Item 2
3. Item 3
4. Item 6

Back to integers vs. floats

The normal division symbol / will always return a floating point number.

6 / 3

2.0

Sometimes, we would prefer to return an integer number. We can this using the // operation:

6 // 3

2

7 // 2

3

The integer division // will always return the quotient from performing long division.

We can get the remainder from integer division using %. This is called modular division.

7 % 2

1

This cell above shows that the remainder of dividing 7 by 2 is 1.

101 // 43

2

101 % 43

15

The two cells above show that 100 divided by 42 has quotient 2 and remainder 16. Let's check this:

43 * 2 + 15

101

Variable assignment in Python

Very often, we want to perform operations on some input that might change. We can define variables using the = symbol:

num = 102
den = 43

We can recall the value of this variable with the variable name:

num

102

den

43

quot = num // den

rem = num % den

quot

2

rem

16

quot*den + rem

102