Why Should I Avoid Decimal Steps in Python's `range()` and How Can I Achieve Similar Results?

Using Decimal Step Values in Range() with Caution

The range() function in Python is commonly used to iterate over a sequence of numbers. However, when attempting to use a decimal step value, such as 0.1, you may encounter an error indicating that the step argument cannot be zero.

Avoid Using Decimal Step Values Directly

It is strongly advised against using decimal step values directly in range(). Floating-point rounding errors can lead to incorrect results, particularly when using small step values. Instead, it is recommended to express the iteration interval in terms of the desired number of points.

Using NumPy's linspace() Function

The NumPy library provides the linspace() function, which allows you to specify a number of points and the endpoints of the range. By utilizing linspace(), you can achieve the following:

import numpy as np

# Get 11 equally spaced points between 0 and 1, including both endpoints
np.linspace(0, 1, 11)

# Get 10 equally spaced points between 0 and 1, excluding the right endpoint
np.linspace(0, 1, 10, endpoint=False)

Using NumPy's arange() Function (with Caution)

If you genuinely require a floating-point step value, NumPy's arange() function can be employed. However, be aware that floating-point rounding errors can still cause issues, as demonstrated in the following example:

import numpy as np

np.arange(0.0, 1.0, 0.1)

In this instance, due to rounding errors, arange() produces a length-4 array instead of the expected length-3 array. Therefore, it is important to use the linspace() function if precision is crucial.

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