[Tutor] script comparing two values

[Mic Forster]

Hi Guys,

I am attempting to fit an expected geometric series of
relative species abundance with an observed set of
relative species abundance. In doing so one has to
determine a constant, k. This is done by iterating the
following equation:

Nmin / N = (k / (1 - k)) * (pow((1 - k),s)) / (1 -
(pow((1 - k),s)) = j

where Nmin is the number of individuals in the least
abundant species, N is the total number of individuals
and s is the number of species. In my example:

Nmin = 1
N = 862
s = 11

Nmin / N = 0.00116 in this example and therefore the
equation:
j = (k / (1 - k)) * (pow((1 - k),s)) / (1 - (pow((1
-k),s)) must also equal 0.00116

Obviously this involves iterating through a list of
values between 0 and 1 so that the program returns a
value, k, when Nmin / N = j (where 0 < k < 1).

This is what I have and I know that it is completely
wrong:

def constant(j):
	result = []
	i = 0.0
	while i is not j:
		result.append(k)
		i, k = (k / (1 - k)((1 - k)^s) / (1 - (1 - k)^s), i
+ 0.0001
	return result
			
SyntaxError: invalid syntax

Any help?
Cheers,
Mic




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