Question

我基本上是在尝试将CSV数据（从另一个python脚本每5分钟更新一次）到Dash应用中以制作实时动画图表。但这似乎没有用。如果最后使用lastmt = os.stat(path).st_mtime修改了csv，我什至得到有什么帮助吗？ 示例代码：

import dash
import dash_core_components as dcc
import dash_html_components as html
import plotly.graph_objs as go
import os
from dash.dependencies import Input, Output
from dash import Dash, callback_context, no_update



import pandas as pd


path = r"D:\jack\StockMarketStuff\OI_Learning_ExcelDataPull\Dash\my_csv_Nf.csv"

lastmt = os.stat(path).st_mtime
print(lastmt)
df = pd.read_csv(path)

df['Time'] = pd.to_datetime(df['Time']).dt.strftime('%H:%M')
df['CoI_Vol_ce'] = df['Chng in OI_ce']/df['Volume_ce']

s=df.set_index('Time')

s = df.groupby(['Time'])['OI_ce', 'OI_pe','CoI_Vol_ce'].sum()
p = df.groupby(['Time'])['CoI_Vol_ce'].sum()

trace1 = go.Line(x=s.index, y=s[('OI_ce')], name='Call OI')
trace2 = go.Line(x=s.index, y=s[('OI_pe')], name='Put OI')


app = dash.Dash()
app.layout = html.Div(children=[
    html.H1(children='OI Anlaysis'),
    html.Div(children='''call put OI graph.'''),
    dcc.Graph(
        id='example-graph',animate=True,
        figure={
            'data': [trace1, trace2],
            'layout':
            go.Layout(title='OI graph', barmode='stack')
        }),dcc.Interval(id='interval', interval=1000, n_intervals=0)
])



@app.callback(Output('example-graph', 'figure'), [Input('interval', 'n_intervals')])
def trigger_by_modify(n):
    path = r"D:\jack\StockMarketStuff\OI_Learning_ExcelDataPull\Dash\my_csv_Nf.csv"

    df = pd.read_csv(path)
    lastmt = os.stat(path).st_mtime
    print(lastmt)
    if os.stat(path).st_mtime > lastmt:




        df['Time'] = pd.to_datetime(df['Time']).dt.strftime('%H:%M')
        df['CoI_Vol_ce'] = df['Chng in OI_ce']/df['Volume_ce']

        s=df.set_index('Time')

        s = df.groupby(['Time'])['OI_ce', 'OI_pe','CoI_Vol_ce'].sum()
        p = df.groupby(['Time'])['CoI_Vol_ce'].sum()

        trace1 = go.Line(x=s.index, y=s[('OI_ce')], name='Call OI')
        trace2 = go.Line(x=s.index, y=s[('OI_pe')], name='Put OI')
        return [trace1,trace2]
    return no_update
if __name__ == '__main__':
    app.run_server(debug=True)

破折号未更新CSV上的图表已修改？

0 个答案: