Python

having trouble with a mathmatical function

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Join Date: Sep 2009

Posts: 50

Reputation: lukerobi is an unknown quantity at this point

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lukerobi

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Junior Poster in Training

having trouble with a mathmatical function

Oct 4th, 2009

lets say i have 2 lists:
lista = [1,2,3,5,6,7]
listb = [4,5,6,7,8,9,10]

The lists can be different lengths, and may not allways be unequal lengths.

The higher average will allways be in listb, so that is the 1 constant we can rely on.

This works for even teams:

 Help with Code Tags 
 Python Syntax (Toggle Plain Text) 
    average = float(sum(lista) + sum(listb)) / \
        float(len(lista) + len(listb))
 
    value = round(abs((average * len(lista)) - sum(lista)))
    average = float(sum(lista) + sum(listb)) / \
        float(len(lista) + len(listb))

    value = round(abs((average * len(lista)) - sum(lista)))

value would return the number i needed to move from listb to lista

i tried this,but it doesnt seem to work:

 Help with Code Tags 
 Python Syntax (Toggle Plain Text) 
    Offset = float(len(listb) - len(lista))    
 
    value = round(((len(lista) * sum(lista)) + \
    (len(lista) * Offset) - \
    (average * len(lista) - \
    (average * Offset))) / \
    (len(lista) * Offset))
    Offset = float(len(listb) - len(lista))    

    value = round(((len(lista) * sum(lista)) + \
    (len(lista) * Offset) - \
    (average * len(lista) - \
    (average * Offset))) / \
    (len(lista) * Offset))

any ideas?

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Join Date: Feb 2007

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Reputation: scru has a spectacular aura about

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scru

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Posting Virtuoso

Oct 6th, 2009

Huh? You've said what you've done, but not what you're trying to do...

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Join Date: Aug 2009

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Reputation: JohnboyUK is an unknown quantity at this point

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JohnboyUK

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2 Lists

Oct 6th, 2009

Is the function a fictitious theory or for a specific reason?

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Join Date: Oct 2004

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Reputation: vegaseat is just really nice

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vegaseat

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DaniWeb's Hypocrite

Oct 7th, 2009

You are getting tangled up in a forest of parenthesis. There is one missing in the mess. It is best to break things into smaller parts ...

 Help with Code Tags 
 python Syntax (Toggle Plain Text) 
list_a = [1,2,3,5,6,7]
list_b = [4,5,6,7,8,9,10]
# for convenience 
list_ab = list_a + list_b
 
average = float(sum(list_ab))/len(list_ab)
offset = float(len(list_b) - len(list_a))
 
a = len(list_a) * sum(list_a)
b = len(list_a) * offset
c = average * len(list_a)
d = average * offset
 
value = (a + b - c - d)/b
 
print value
print round(value)
list_a = [1,2,3,5,6,7]
list_b = [4,5,6,7,8,9,10]
# for convenience 
list_ab = list_a + list_b

average = float(sum(list_ab))/len(list_ab)
offset = float(len(list_b) - len(list_a))

a = len(list_a) * sum(list_a)
b = len(list_a) * offset
c = average * len(list_a)
d = average * offset

value = (a + b - c - d)/b

print value
print round(value)