np.min() and np.max() in NumPy - Step-by-Step Execution

Concept Flow - np.min() and np.max()

Start with array

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Call np.min()

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Scan all elements

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Find smallest value

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Return min value

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Call np.max()

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Scan all elements

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Find largest value

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Return max value

np.min() scans the array to find the smallest number and returns it. np.max() scans to find the largest number and returns it.

Execution Sample

NumPy

import numpy as np
arr = np.array([3, 7, 1, 9, 4])
min_val = np.min(arr)
max_val = np.max(arr)
print(min_val, max_val)

This code finds the smallest and largest numbers in the array and prints them.

Execution Table

Step	Function Call	Array Elements	Operation	Result
1	np.min(arr)	[3, 7, 1, 9, 4]	Scan all elements to find smallest	1
2	np.max(arr)	[3, 7, 1, 9, 4]	Scan all elements to find largest	9
3	Print results	min_val=1, max_val=9	Output values	1 9

💡 All elements scanned; min and max values found and printed.

Variable Tracker

Variable	Start	After np.min()	After np.max()	Final
arr	[3,7,1,9,4]	[3,7,1,9,4]	[3,7,1,9,4]	[3,7,1,9,4]
min_val	undefined	1	1	1
max_val	undefined	undefined	9	9

Key Moments - 2 Insights

Why does np.min(arr) return 1 and not the first element 3?

np.min() checks every element in the array (see execution_table step 1) and returns the smallest value found, which is 1, not just the first element.

Does np.max() change the original array?

No, np.max() only reads the array to find the largest value (execution_table step 2). It does not modify the array.

Visual Quiz - 3 Questions

Look at the execution table, what is the result of np.min(arr) at step 1?

A 9

B 3

C 1

D 7

💡 Hint

Check the 'Result' column in execution_table row for step 1.

At which step does the code print the min and max values?

A Step 3

B Step 2

C Step 1

D No print step

💡 Hint

Look for the step with 'Print results' in the 'Function Call' column.

If the array was [5, 5, 5], what would np.max(arr) return?

A 0

B 5

C 15

D Error

💡 Hint

np.max() returns the largest element; check variable_tracker for max_val.

Concept Snapshot

np.min(array) returns the smallest value in the array.
np.max(array) returns the largest value.
Both scan all elements without changing the array.
Useful to quickly find range boundaries.
Syntax: min_val = np.min(arr), max_val = np.max(arr)

Full Transcript

This lesson shows how np.min() and np.max() work by scanning an array to find the smallest and largest values. We start with an array of numbers. Calling np.min() checks each number and returns the smallest one. Calling np.max() does the same but returns the largest. The original array stays the same. We track variables min_val and max_val as they get assigned. The execution table shows each step clearly: first finding min, then max, then printing results. Common confusions include thinking np.min() returns the first element or that np.max() changes the array. The quiz tests understanding of these steps and results.