I'm trying to do a logistic map using the code below, but I'm struggling with making a scatter plot because I keep getting this error: "scatter() missing 1 required positional argument: 'y'". I understand I'm missing another 'y' but I don't know what I'm supposed to add.

allys = []

for r in np.arange(0.001, 4, 0.001):
    y = np.random.rand()
    for t in range(1000):
        y = r * y * (1 - y)
        if t > 959:
            allys.append(y)
        
plt.scatter(allys, color = 'black', s = 1) #<--error from here
plt.xticks(np.arange(0, 4, 0.5))
plt.show()

TypeError: scatter() missing 1 required positional argument: 'y'"

I'm trying to do a logistic map using the code below, but I'm struggling with making a scatter plot because I keep getting this error: "scatter() missing 1 required positional argument: 'y'". I understand I'm missing another 'y' but I don't know what I'm supposed to add.

allys = []

for r in np.arange(0.001, 4, 0.001):
    y = np.random.rand()
    for t in range(1000):
        y = r * y * (1 - y)
        if t > 959:
            allys.append(y)
        
plt.scatter(allys, color = 'black', s = 1) #<--error from here
plt.xticks(np.arange(0, 4, 0.5))
plt.show()

TypeError: scatter() missing 1 required positional argument: 'y'"

• python
• jupyter
• scatter-plot

1 Answer 1

You are only passing in allys. You need to also define a second array for the x values and pass that into plt.scatter as it requires x and y coordinates to work.

E.g.

allys = []
allxs = []

for r in np.arange(0.001, 4, 0.001):
    y = np.random.rand()
    for t in range(1000):
        y = r * y * (1 - y)
        if t > 959:
            allys.append(y)
            allxs .append(r) 

plt.scatter(allxs , allys, color='black', s=1)