Python - 如何使用字典正确绘制折线图？

Question

I am trying to plot a line graph to show the trends of each key of a dictionary in Jupyter Notebook with Python. This is what I have in the k_rmse_values variable as shown below:

k_rmse_values = {'bore': {1: 8423.759328233446, 3: 6501.928933614838, 5: 6807.187615513473, 7: 6900.29659028346, 9: 7134.8868708101645}, 'city-mpg': {1: 4265.365592771621, 3: 3865.0178306330113, 5: 3720.409335758634, 7: 3819.183283405616, 9: 4219.677972675927}, 'compression-rate': {1: 7016.906657495168, 3: 7319.354017489066, 5: 6301.624922763969, 7: 6133.006310754547, 9: 6417.253959732598}, 'curb-weight': {1: 3950.9888180049306, 3: 4201.343428000144, 5: 4047.052502155118, 7: 3842.0974736649846, 9: 3943.9478256384205}, 'engine-size': {1: 2853.7338453331627, 3: 2793.6254775629623, 5: 3123.320055069605, 7: 2941.73029681235, 9: 2931.996240628853}, 'height': {1: 6330.178232877807, 3: 7049.500497198366, 5: 6869.570862695864, 7: 6738.641089739572, 9: 6344.062937760911}, 'highway-mpg': {1: 4826.0580187146525, 3: 3510.253629329685, 5: 3379.2250123364083, 7: 4044.271135312068, 9: 4462.027046251678}, 'horsepower': {1: 3623.6389886411143, 3: 4294.825669466819, 5: 4778.254807521257, 7: 4730.5387015 14935, 9: 4662.8601512508885}, 'length': {1: 4952.798701744297, 3: 5403.624431188139, 5: 5500.731909846179, 7: 5103.4515274528885, 9: 4471.077661709427}, 'normalized-losses': {1: 9604.929081466453, 3: 7494.820436511842, 5: 6391.912634697067, 7: 6699.853883298577, 9: 6861.6389834002875}, 'peak-rpm': {1: 8041.2366213164005, 3: 7502.080095843049, 5: 6521.863037752326, 7: 6869.602542315512, 9: 6884.533017667794}, 'stroke': {1: 10330.231237489314, 3: 8947.585146097614, 5: 6973.912792744113, 7: 7266.333478250421, 9: 7026.017456146411}, 'wheel-base': {1: 2797.4144312203725, 3: 3392.8627620671928, 5: 4238.25624378706, 7: 4456.687059524217, 9: 4426.032222634904}, 'width': {1: 2849.2691940215127, 3: 4076.59327053035, 5: 3979.9751617315405, 7: 3845.3326184519606, 9: 3687.926625900343}}

When I used this code to plot

for k,v in k_rmse_values.items():
x = list(v.keys())
y = list(v.values())

plt.plot(x,y)
plt.xlabel('k value')
plt.ylabel('RMSE')

and it doesn't plot from 1 to 9 in order; it gives this graph

it plots in this k-value order 1, 3, 9 , 5, 7

I have spent hours on this problem and still can't figure out a way to do it. Your help with this would be greatly appreciated.

Answer 1

One solution is to sort the keys and get the matching values:

for k,v in k_rmse_values.items():
  xs = list(v.keys()).sort()
  ys = [v[x] for x in xs]

# Note I renamed these arrays so following uses should be changed accordingly