在“Dash”中创建基于用户选择的图形

import dash
import dash_core_components as dcc
import dash_html_components as html
from dash.dependencies import Input, Output

# 创建Dash应用
app = dash.Dash(__name__)

# 创建布局
app.layout = html.Div([
    html.H1("基于用户选择的图形"),
    dcc.Dropdown(
        id='graph-type',
        options=[
            {'label': '折线图', 'value': 'line'},
            {'label': '柱状图', 'value': 'bar'},
            {'label': '散点图', 'value': 'scatter'}
        ],
        value='line'
    ),
    dcc.Graph(id='graph')
])

# 添加回调函数
@app.callback(
    Output('graph', 'figure'),
    [Input('graph-type', 'value')]
)
def update_graph(graph_type):
    if graph_type == 'line':
        # 创建折线图的数据和布局
        data = [{'x': [1, 2, 3], 'y': [4, 1, 2], 'type': 'line'}]
        layout = {'title': '折线图'}
    elif graph_type == 'bar':
        # 创建柱状图的数据和布局
        data = [{'x': [1, 2, 3], 'y': [2, 4, 1], 'type': 'bar'}]
        layout = {'title': '柱状图'}
    elif graph_type == 'scatter':
        # 创建散点图的数据和布局
        data = [{'x': [1, 2, 3], 'y': [3, 1, 4], 'type': 'scatter', 'mode': 'markers'}]
        layout = {'title': '散点图'}
    
    return {'data': data, 'layout': layout}

# 运行应用
if __name__ == '__main__':
    app.run_server(debug=True)