Python Variables

Last modified on: October 20, 2024

<h3>Python Variables Overview</h3>
<p>In Python, variables are used to store data values. Unlike some other languages, Python variables don&rsquo;t require explicit declaration or type definition; the type is inferred based on the value assigned.</p>
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<p><strong>Variable Assignment</strong>: No need for a data type declaration; Python automatically determines the type.</p>
<pre class="language-python"><code>x = 10        # Integer
name = "John" # String
pi = 3.14     # Float
</code></pre>
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<p><strong>Dynamic Typing</strong>: Variables can change their type dynamically.</p>
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<pre class="language-python"><code>x = 10        # Initially an integer
x = "Hello"   # Now it's a string
</code></pre>
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<p><strong>Multiple Assignment</strong>: You can assign values to multiple variables in a single line.</p>
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<pre class="language-python"><code>a, b, c = 5, 10, 15</code></pre>
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<p><strong>Global and Local Variables</strong>: Variables declared inside a function are local by default. Use the <code>global</code> keyword to modify a global variable inside a function.</p>
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<pre class="language-python"><code>x = 5  # Global variable

def example():
    global x
    x = 10  # Modify global x inside the function
</code></pre>
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<p><strong>Naming Rules</strong>: Variable names can only contain letters, digits, and underscores. They can&rsquo;t start with a digit and are case-sensitive.</p>
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<h3>Python Variables Example</h3>
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<pre class="language-python"><code># Defining variables
age = 25
name = "Alice"
is_student = True

# Displaying variable values
print(f"Name: {name}, Age: {age}, Is a student: {is_student}")

# Reassigning a variable
age = 30
print(f"{name} is now {age} years old")

# Multiple assignment
a, b, c = 1, 2.5, "Python"
print(a, b, c)
</code></pre>
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