Merge pull request #4 from Redume/feat/improved-graphics

Feat/improved graphics

chart/function/create_chart.py

@@ -6,6 +6,8 @@ based on historical data retrieved from the database.
 from datetime import datetime
 
 from matplotlib import pyplot as plt
+from scipy.interpolate import make_interp_spline
+import numpy as np
 
 from function.gen_unique_name import generate_unique_name
 from database.server import create_pool
@@ -44,7 +46,8 @@ async def create_chart(
 	async with pool.acquire() as conn:
 		data = await conn.fetch(
 			'SELECT date, rate FROM currency '
-            'WHERE (date BETWEEN $1 AND $2) AND from_currency = $3 AND conv_currency = $4 ORDER BY date',
+			'WHERE (date BETWEEN $1 AND $2) ' +
+			'AND from_currency = $3 AND conv_currency = $4 ORDER BY date',
 			start_date_obj,
 			end_date_obj,
 			from_currency.upper(),
@@ -55,32 +58,43 @@ async def create_chart(
 		return None
 
 	date, rate = [], []
-    fig = plt.gcf()
 
 	for row in data:
-        date.append(str(row['date']))
-        rate.append(row['rate'])
-        width = 18.5 + (len(date) // 5) * 3 
-        fig.set_size_inches(width, 9.5)
+		date.append(row[0])
+		rate.append(row[1])
 
+	spline = make_interp_spline(range(len(date)), rate, k=2)
+	x = np.arange(len(date))
 
-    if rate[0] < rate[-1]:
-        plt.plot(date, rate, color='green', marker='o')
-    elif rate[0] > rate[-1]:
-        plt.plot(date, rate, color='red', marker='o')
-    else:
-        plt.plot(date, rate, color='grey')
+	newx_2 = np.linspace(0, len(date) - 1, 200)
+	newy_2 = spline(newx_2)
+	fig, ax = plt.subplots(figsize=(15, 6))
 
-    plt.xlabel('Date')
-    plt.ylabel('Rate')
+	for label in (ax.get_xticklabels() + ax.get_yticklabels()):
+		label.set_fontsize(10)
 
+	ax.set_xticks(np.linspace(0, len(date) - 1, 10))
+	ax.set_xticklabels(
+		[
+			date[int(i)].strftime('%Y-%m-%d') 
+			for i in np.linspace(0, len(date) - 1, 10).astype(int)
+		]
+		)
 
 	name = await generate_unique_name(
 		f'{from_currency.upper()}_{conv_currency.upper()}',
 		datetime.now()
 	)
 
-    fig.savefig(f'../charts/{name}.png')
+	
+	if rate[0] < rate[-1]:
+		plt.plot(newx_2, newy_2, color='green')
+	elif rate[0] > rate[-1]:
+		plt.plot(newx_2, newy_2, color='red')
+	else:
+		plt.plot(newx_2, newy_2, color='grey')
+
+	plt.savefig(f'../charts/{name}.png')
 	fig.clear()
 
 	return name

chart/requirements.txt

@@ -5,3 +5,5 @@ fastapi[standard]~=0.115.2
 starlette~=0.40.0
 user_agents==2.2.0
 asyncpg~=0.30.0
+scipy~=1.15.2
+numpy~=2.2.0