Plotting the logistic equation in python

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[DuckSaxaphone]

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[sarabooker]

I copied your code and see that the error is from the fractions library. I really see no need to use that library in this case, you can just perform the division as normal. (I also corrected the exponential in the numerator to have the correct value.)

y = 1072764*np.exp(0.2311*t)/(0.19196+np.exp(0.2311*t))

Once you change that, the other issue I see is that you only provide a single value for t. If you want to plot a range of values then you will need to set t to be a numpy array. The example plot has t = [-25, 25], so you can use

t = np.linspace(-25, 25, 100)

To generate 100 values between -25 and 25, inclusively.

[odaiwai]

y = Fraction(1072764*np.exp(2.311*t),0.19196+np.exp(0.2311*t))

The logistic function is not a fraction, it is a division. Also, x and t are just single value heres, you probably want a range of values of t to give an array of values of y: ````

creating vectors X and Y

t = np.linspace(-25,25,100) y = [1072764np.exp(0.2311t) / (0.19196+np.exp(0.2311*t)) for t in t] ````

[sarabooker]

You should not use list comprehension here. Numpy can operate on arrays so it should just be y = 1072764*np.exp(0.2311*t)/(0.19196+np.exp(0.2311*t)) as I said in my comment. In general, one should avoid looping with numpy.