使用python中的panda库和Dash Plotly创建带有标签和值的下拉列表

Question

我在Python中使用熊猫库从csv文件读取并填充Dropdown。 我的应用程序使用Dash Plotly创建HTML Web界面。 我只填写了下拉列表的值，下拉列表的标签与这些值相同。 如何将标签更改为csv文件中的文本？

available_rpi.csv

ip,name
192.168.1.6,"Virtual I²C (192.168.1.6)"
192.168.1.102,"GPS UART (192.168.1.102)"
192.168.1.106,"Ultrasonic I²C (192.168.1.103)"

python脚本：

import dash,requests,pandas as pd

df = pd.read_csv('available_rpi.csv', usecols = ['ip','name'])
available_rpi = df['ip'].unique()

app.layout = html.Div( [
    html.H1(children='RESENSE'),
    html.Div(children='''RESENSE: Transparent Record and Replay in the Internet of Things (IoT).'''),
    # html.Div(['Name : ', dcc.Input(id='input',value='ACC',type='text') ]),
    # dcc.Markdown(''' '''),
    html.Label('Raspberry Pi'),
    dcc.Dropdown(
        id = "input",
        options=[{'label': i, 'value': i} for i in available_rpi],
        value=''
    ),
    html.Div(id='output'),
    #   Graph for arriving data (static)
    dcc.Graph(id='data', animate=True),
    dcc.Interval(id='graph-update',interval=2*1000)
    ])

Answer 1

您应该使用orient='records' .csv文件存储为词典列表，然后使用列表推导为Dropdown组件设置选项：

import dash
import pandas as pd
import dash_core_components as dcc
import dash_html_components as html

available_rpi = pd.read_csv('available_rpi.csv').to_dict(orient='records')

app = dash.Dash(__name__)

app.layout = html.Div([

    html.H1(children='RESENSE'),

    html.Div(children='''RESENSE: Transparent Record and Replay in the Internet of Things (IoT).'''),

    html.Label('Raspberry Pi'),

    dcc.Dropdown(
        id = "input",
        options=[{'label': i['name'], 'value': i['ip']} for i in available_rpi],
        value=''
    ),

    html.Div(id='output'),

    #Graph for arriving data (static)
    dcc.Graph(id='data', animate=True),

    dcc.Interval(id='graph-update',interval=2*1000)

])

if __name__ == '__main__':
    app.run_server()

Answer 2

我必须使用字典。

available_rpi = pd.read_csv('available_rpi.csv', header=None, dtype={0: str}).set_index(0).squeeze().to_dict()
#print("Raspberry Pi's available:")
#for key, car in available_rpi.items():
#    print('{} : {}'.format(key, car))

app.layout = html.Div( [
    html.H1(children='RESENSE'),
    html.Div(children='''RESENSE: Transparent Record and Replay in the Internet of Things (IoT).'''),
    # html.Div(['Name : ', dcc.Input(id='input',value='ACC',type='text') ]),
    # dcc.Markdown(''' '''),
    html.Label('Raspberry Pi'),
    dcc.Dropdown(
        id = "input",
        options=[{'label': v, 'value': k} for k, v in available_rpi.items()],
        value=''
    ),
    html.Div(id='output'),
    #   Graph for arriving data (static)
    dcc.Graph(id='data', animate=True),
    dcc.Interval(id='graph-update',interval=2*1000)
    ])

Answer 3

用熊猫以不同的方式读取CSV数据并将其存储在字典中怎么样？

import dash
import pandas as pd
import dash_core_components as dcc
import dash_html_components as html

df = pd.read_csv('available_rpi.csv', usecols = ['ip','name'])
available_rpi = df.to_dict('records')

app = dash.Dash(__name__)

app.layout = html.Div( [
    html.H1(children='RESENSE'),
    html.Div(children='''RESENSE: Transparent Record and Replay in the Internet of Things (IoT).'''),
    # html.Div(['Name : ', dcc.Input(id='input',value='ACC',type='text') ]),
    # dcc.Markdown(''' '''),
    html.Label('Raspberry Pi'),
    dcc.Dropdown(
        id = "input",
        options=[{'label': i['name'], 'value': i['ip']} for i in available_rpi],
        value=''
    ),
    html.Div(id='output'),
    #   Graph for arriving data (static)
    dcc.Graph(id='data', animate=True),
    dcc.Interval(id='graph-update',interval=2*1000)
    ])

if __name__ == '__main__':
    app.run_server()