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45 lines
1.6 KiB
HTML
45 lines
1.6 KiB
HTML
<pre>
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DataFrame customers
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+-------------+--------+
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| Column Name | Type |
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+-------------+--------+
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| customer_id | int |
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| name | object |
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| email | object |
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+-------------+--------+
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</pre>
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<p>There are some duplicate rows in the DataFrame based on the <code>email</code> column.</p>
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<p>Write a solution to remove these duplicate rows and keep only the <strong>first</strong> occurrence.</p>
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<p>The result format is in the following example.</p>
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<p> </p>
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<pre>
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<strong class="example">Example 1:</strong>
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<strong>Input:</strong>
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+-------------+---------+---------------------+
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| customer_id | name | email |
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+-------------+---------+---------------------+
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| 1 | Ella | emily@example.com |
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| 2 | David | michael@example.com |
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| 3 | Zachary | sarah@example.com |
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| 4 | Alice | john@example.com |
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| 5 | Finn | john@example.com |
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| 6 | Violet | alice@example.com |
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+-------------+---------+---------------------+
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<strong>Output: </strong>
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+-------------+---------+---------------------+
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| customer_id | name | email |
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+-------------+---------+---------------------+
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| 1 | Ella | emily@example.com |
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| 2 | David | michael@example.com |
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| 3 | Zachary | sarah@example.com |
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| 4 | Alice | john@example.com |
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| 6 | Violet | alice@example.com |
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+-------------+---------+---------------------+
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<strong>Explanation:</strong>
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Alic (customer_id = 4) and Finn (customer_id = 5) both use john@example.com, so only the first occurrence of this email is retained.
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</pre>
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