在 python 中使用熊猫库和 Dash Plotly 创建带有标签和值的下拉列表

Question

我在 Python 中使用 panda 库从 csv 文件中读取并填充下拉列表。我的应用程序使用 Dash Plotly 创建一个 HTML 网络界面。我只填充下拉列表的值，下拉列表的标签与值相同。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' 将您的 .csv 文件存储为字典列表，然后使用列表理解来设置您的下拉组件选项：

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

我得用字典....

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 pandas 以稍微不同的方式读取 CSV 数据并将其存储在字典中如何？

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()

在 python 中使用熊猫库和 Dash Plotly 创建带有标签和值的下拉列表

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