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Leer Advanced Arithmetic | Numbers
Data Types in Python

bookAdvanced Arithmetic

A step beyond basics: learn how Python handles floor division and modulo (including negatives) and get a quick tour of the built-in math module you'll use for everyday numeric work.

Floor Division (//)

Returns the floor of the exact quotient — i.e., rounds down toward −∞.

12
print(7 // 3) # 2 print(-7 // 3) # -3 (floors down: -2.333... → -3)
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Why it matters: indexing chunks/pages, time splitting (hours from seconds), and any "how many full groups fit" calculation.

Modulo %

Gives the remainder in the identity:

a == (a // b) * b + (a % b)

In Python, the remainder has the same sign as the divisor b.

123
print(7 % 3) # 1 print(-7 % 3) # 2 (because -7 == (-3)*3 + 2) print(7 % -3) # -2 (because 7 == (-2)*(-3) + -2)
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Why it matters: "every Nth" item, wrap-around (e.g., clock arithmetic), cycling through buckets.

Quick Note on Rounding

Built-in round(x, ndigits) uses "round half to even".

12
print(round(2.5), round(3.5)) # 2 4 print(round(2.675, 2)) # 2.67 (binary float nuance)
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The math Module (essentials)

Import once and access many handy functions/constants.

123456
import math print(math.floor(2.9), math.ceil(2.1), math.trunc(-2.9)) # 2 3 -2 print(math.sqrt(9)) # 3.0 print(math.pi, math.e) # 3.14159... 2.71828... print(math.isfinite(1.0), math.isfinite(float('inf'))) # True False
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  • floor/ceil/trunc: down / up / toward zero (watch negatives);
  • sqrt: square root (float result);
  • pi, e: common constants;
  • isfinite, isnan, isinf: sanity checks for special float values.

1. What value will this code output?

2. What value will this code output?

3. Which call returns -3?

question mark

What value will this code output?

Select the correct answer

question mark

What value will this code output?

Select the correct answer

question mark

Which call returns -3?

Select the correct answer

Was alles duidelijk?

Hoe kunnen we het verbeteren?

Bedankt voor je feedback!

Sectie 1. Hoofdstuk 3

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bookAdvanced Arithmetic

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A step beyond basics: learn how Python handles floor division and modulo (including negatives) and get a quick tour of the built-in math module you'll use for everyday numeric work.

Floor Division (//)

Returns the floor of the exact quotient — i.e., rounds down toward −∞.

12
print(7 // 3) # 2 print(-7 // 3) # -3 (floors down: -2.333... → -3)
copy

Why it matters: indexing chunks/pages, time splitting (hours from seconds), and any "how many full groups fit" calculation.

Modulo %

Gives the remainder in the identity:

a == (a // b) * b + (a % b)

In Python, the remainder has the same sign as the divisor b.

123
print(7 % 3) # 1 print(-7 % 3) # 2 (because -7 == (-3)*3 + 2) print(7 % -3) # -2 (because 7 == (-2)*(-3) + -2)
copy

Why it matters: "every Nth" item, wrap-around (e.g., clock arithmetic), cycling through buckets.

Quick Note on Rounding

Built-in round(x, ndigits) uses "round half to even".

12
print(round(2.5), round(3.5)) # 2 4 print(round(2.675, 2)) # 2.67 (binary float nuance)
copy

The math Module (essentials)

Import once and access many handy functions/constants.

123456
import math print(math.floor(2.9), math.ceil(2.1), math.trunc(-2.9)) # 2 3 -2 print(math.sqrt(9)) # 3.0 print(math.pi, math.e) # 3.14159... 2.71828... print(math.isfinite(1.0), math.isfinite(float('inf'))) # True False
copy
  • floor/ceil/trunc: down / up / toward zero (watch negatives);
  • sqrt: square root (float result);
  • pi, e: common constants;
  • isfinite, isnan, isinf: sanity checks for special float values.

1. What value will this code output?

2. What value will this code output?

3. Which call returns -3?

question mark

What value will this code output?

Select the correct answer

question mark

What value will this code output?

Select the correct answer

question mark

Which call returns -3?

Select the correct answer

Was alles duidelijk?

Hoe kunnen we het verbeteren?

Bedankt voor je feedback!

Sectie 1. Hoofdstuk 3
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