# 3 Symbols in Data Science (part 1) (Math & Python) Flashcards

1 Name, use and example of =

Equality

5 = 2+3

5 is equal to 2+3

2 Name, use example and equivalent in Python of ≠

Inequality

5 ≠ 4

5 is not equal to 4

In Python:

!= 3!=4

2.1 Outcome of:

print(5!=4)

True

3 Name, use and example of ≈

approximation

x ≈ y

x is approximately equal to y

4 What does the /= operator mean in Python?

It’s an assignment operator shorthand for / and =

x /= 3 # equivalent to x = x / 3

4.1 Outcome of:

x = 1

x/=4

x

0.25

5 Name, use and example of >

greater than

5 > 4

5 is greater than 4

5.1 Outcome of:

5>4

True

6 Name, how to read and example of

less than

4 < 5

4 is less than 5

6.1 Outcome of:

5<4

False

7 Name, how to read, example, and equivalent in Python of≥

greater than or equal to

5 ≥ 4,

x ≥ y means x is greater than or equal to y

Python: 5>=4

Outcome of:

a =[0,0]

b=[0,1]

a>=b

False

8 Name, how to read, example, and equivalent in Python of ≤

less than or equal to

4 ≤ 5,

x ≤ y x is less than or equal to y

Python: 4<=4

8.1 Outcome of:

a =[0,0]

b=[0,1]

a<=b

9 Name, use in Maths and Python and examples of: ( )

Parentheses

Maths:order of operation. calculate expression inside first

Python: order of operation, tuples, generator expressions, function calls and other syntax

2 × (3+5) = 16

a=(1,4,5) #tuple (unchangeable)

9.1 Outcome of:

print(2* (3+5) )

print(2*3+5)

16

11

10 Name, use in Maths and Python and examples of:[ ]

Brackets

Maths: order of operations.calculates expression inside first

Python: order of operation, to define mutable data types - lists, list comprehensions and for indexing/lookup/slicing

10.1 Outcome of:

print[2* [3+5] ]

TypeError: ‘builtin_function_or_method’ object is not subscriptable

11 Name and read: +

1 + 1 = 2

Addition

One plus one equals two

1 + 1 = 2

12 Name and read: −

Subtraction

2 − 1 = 1

Two minus one equals one

13 Name and example of: ±

plus and minus

3 ± 5 = 8 or -2

14 Name and example of: ±

±

minus - plus

both minus and plus operations

3 ∓ 5 = -2 or 8

15 Name,use,read and Python uses of *

2 * 3 = 6

Asterisk

Multiplication

2 * 3 = 6

Two multiplied by three is equal to six

Python: Multiplication and unpacking

16 Name,use of ⋅

Multiplication dot

2 ⋅ 3 = 6

17 Name,use,read of:÷

6 ÷ 2 = 3

Division sign

Six divided by 2 equals three

18 Name and use in Maths and Python of /

Slash

Maths: Division

Python: Division, for file paths

6 / 2 = 3

p = PurePath(‘/etc’)

18 Name and use of —

horizontal line

division / fraction

19 Name and use of % in Maths and Python

Maths: Percentage

Python:Modulo

Python: remainder calculation

Python: 7%2 = 1

Maths: 1% = 1/100

10% × 30 = 3

20 Name and use of .

Period, decimal point, decimal separator

2.56 = 2+56/100

21 Name and use of a^b

Power Exponent

2^3 = 8

22 Name and use of a^b

Caret

Exponent

2 ^ 3 = 8

22 Name and use of √a

square root

√a ⋅ √a = a

√9 = ±3

22 Name and use of 3√a

cube root

3√a ⋅ 3√a ⋅ 3√a = a

3√8 = 2

23 Name and use of n√a

n-th root (radical)

for n=3, n√8 = 2

23.1 Calculate for n=7, n√8 = 2

#Answer: n = 7 8**(1/n)

24 Name and use of ‰

Per-mille

1‰ = 1/1000 = 0.1%

10‰ × 30 = 0.3