Int, Double, Float number types in Swift - Step-by-Step Execution

Concept Flow - Int, Double, Float number types

Start

↓

Declare Int variable

↓

Declare Double variable

↓

Declare Float variable

↓

Use variables in calculations

↓

Print results

↓

End

This flow shows declaring Int, Double, and Float variables, using them, and printing their values.

Execution Sample

Swift

let age: Int = 30
let price: Double = 19.99
let temperature: Float = 36.6
print(age)
print(price)
print(temperature)

This code declares three variables of different number types and prints their values.

Execution Table

Step	Action	Variable	Value	Output
1	Declare Int variable 'age'	age	30
2	Declare Double variable 'price'	price	19.99
3	Declare Float variable 'temperature'	temperature	36.6
4	Print 'age'	age	30	30
5	Print 'price'	price	19.99	19.99
6	Print 'temperature'	temperature	36.6	36.6

💡 All variables declared and printed, program ends.

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	Final
age	undefined	30	30	30	30
price	undefined	undefined	19.99	19.99	19.99
temperature	undefined	undefined	undefined	36.6	36.6

Key Moments - 2 Insights

Why do we use Int for 'age' but Double for 'price'?

Because 'age' is a whole number without decimals, Int is perfect. 'price' can have decimals, so Double is used. See steps 1 and 2 in execution_table.

Why is 'temperature' declared as Float and not Double?

Float uses less memory and is enough for 'temperature' precision here. Double is more precise but uses more space. See step 3 in execution_table.

Visual Quiz - 3 Questions

Look at the execution_table, what is the value of 'price' after step 2?

A 19.99

B 30

C 36.6

D undefined

💡 Hint

Check the 'price' value in row with step 2 in execution_table.

At which step is the 'temperature' variable declared?

A Step 1

B Step 3

C Step 2

D Step 4

💡 Hint

Look for the action 'Declare Float variable' in execution_table.

If we change 'age' to 30.5, what will happen?

A It will convert to Double silently.

B It will store 30.5 as Int automatically.

C It will cause a type error because Int cannot hold decimals.

D It will store 30.5 as Float.

💡 Hint

Recall that Int only holds whole numbers, see step 1 in execution_table.

Concept Snapshot

Int, Double, Float in Swift:
- Int: whole numbers, no decimals
- Double: decimal numbers, high precision
- Float: decimal numbers, less precision, uses less memory
Use Int for counts, Double for money, Float for less precise decimals
Declare with let/var and type annotation

Full Transcript

This visual execution shows how Swift handles three number types: Int, Double, and Float. First, an Int variable 'age' is declared with value 30, suitable for whole numbers. Next, a Double variable 'price' is declared with 19.99, allowing decimals with high precision. Then, a Float variable 'temperature' is declared with 36.6, which uses less memory but less precision. Each variable is printed, showing their stored values. Key points include choosing Int for whole numbers, Double for precise decimals, and Float for less precise decimals. Trying to assign a decimal to Int causes an error. This helps beginners understand number types and their uses in Swift.