Algorithm to encode any text in the optimal chemical symbols representation. Full article at http://gabgav.com/writing-with-elements/

symbolencoder.py

# import elements database
from periodic import elements

# Exclude last 6 new elements, which have 3 letters provisional names
# And parse everything into a tuples array
elements = [(element.symbol, element.name) for element in elements[:-6]]


def print_elements(elements_array):
    """Prints an array of elements with brackets, and prints fake elements as normal text"""
    print ''.join(
        [
            '[' + element[0] + ']' if element[1] != 'fake' else element[0]
            for element in elements_array
        ]
    )


def encode_one(left):
    """
    Internal recursive function. Algorithm:
    encode(string):
        list options
        for element in (elements + fake element made of first letter):
            if string starts with element:
                if element isn't fake or options is empty:
                    if string equals to element:
                        append element to options
                    else:
                        for option in encode(string - element):
                            append [element] + option to options
        return options
    """
    options = []
    for element in elements + [(left[:1], 'fake')]:
        if left.startswith(element[0].lower()):
            if element[1] != 'fake' or options == []:
                if len(left) == len(element[0]):
                    options.append([element])
                else:
                    for option in encode_one(left[len(element[0]):]):
                        options.append([element] + option)
    return options


def score(option):
    """Calculates score of an option"""
    fakes = 0
    shorts = 0
    longs = 0
    
    for pos in option:
        if pos[1] == 'fake':
            fakes += len(pos[0])
        elif len(pos[0]) == 2:
            longs += 1
        else:
            shorts += 1
            
    return shorts**2 + longs**2.5 - fakes**3


def sort_options(options):
    """Sorts the options based on the score function"""
    options = [(score(option), option) for option in options]
    options.sort()
    return [option[1] for option in options]


def encode(string):
    """Returns all the valid options"""
    return sort_options(encode_one(string.lower()))


def print_options(string):
    for option in encode(string):
        print_elements(option)

print_options('Hello world!')