How do I convert all of the items in a list to floats?

Breakdown: different approaches and their nuances

Transform string to float: the classic way

Use map function to call float on every string:

floats = list(map(float, your_list)) # Back to basics!
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For the hungry data-beast: NumPy

When dealing with impossibly long lists for scientific calculations, NumPy comes to the rescue with its furious speed:

import numpy as np
float_array = np.array(your_list, dtype=np.float_) # I am speed.🏎💨
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dtype is strictly defined for pure-blooded float conversion.

In-place modifications: going rogue with enumerate

Change the elements inside your original list without creating a new one:

for index, value in enumerate(your_list): # Fake ID, please!🔖
    your_list[index] = float(value)
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Key considerations for surprising hurdles on the road

Test before you leap: pre-check data types

Before jumping to convert, check if the leap is safe. Not everything that glitters is float:

all_items_valid = all(isinstance(item, (int, str)) and item.replace('.','',1).isdigit() for item in your_list) # Do you float?🏊‍♂️
if all_items_valid: 
    floats = [float(i) for i in your_list] 
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Beware of the shadow: don't shadow built-in names

Choose variable names wisely. Naming your pet python float, str or list might lead to an identity crisis!

Race of efficiency: list comprehension, map or numPy?

While list comprehension and map take the cake for readability, numpy has unmatched speed when it comes to big-numbers competitions.