Python - coordinates plotting

Question

i need advice. In my DB, i have x points and y points in form:

df = pd.read_sql_table('table', cnx)

id	curves
1	[(x,y),(x,y),(x,y) etc.]
2	[(x,y),(x,y),(x,y) etc.]

type(df['curves']) #pandas.core.series.Series

And I would like to try to plot Line Graph.

I try several solutions. but nothing worked for me.

data = df['curves']
plt.plot(*zip(*data))
plt.show()

or

data_in_array = np.array(data)
transposed = data_in_array.T
x,y = transposed #but here i got error - not enough values to unpack (expected 2, got 1)

Please advice

user_5120049 · Answer

Explode the curves list column

df = df.explode('curves').reset_index()

Create separate x and y columns

df['curves_x'] = df.curves.str[0]
df['curves_y'] = df.curves.str[1]

Plot using seaborn

import seaborn as sns
import matplotlib.pyplot as plt

sns.lineplot(data=df, x='curves_x', y='curves_y', hue='id')
plt.show()

To understand better, let's take some sample data,

   id                          curves
0   1  [(10, 20), (20, 30), (30, 50)]
1   2  [(10, 10), (20, 40), (30, 20)]

Explode the column and reset the index

   id    curves
0   1  (10, 20)
1   1  (20, 30)
2   1  (30, 50)
3   2  (10, 10)
4   2  (20, 40)
5   2  (30, 20)

Create x and y columns

   id    curves  curves_x  curves_y
0   1  (10, 20)        10        20
0   1  (20, 30)        20        30
0   1  (30, 50)        30        50
1   2  (10, 10)        10        10
1   2  (20, 40)        20        40
1   2  (30, 20)        30        20

The plot will look like this

Python - coordinates plotting

1 Answers