如何显示熊猫数据帧，其中包含我使用达世币上传组件上传的文件

Question

我按照本指南和文档将 excel 文件上传到仪表板：https://dash.plot.ly/dash-core-components/upload

我想知道如何在熊猫数据框中显示上传结果。我的代码概述如下。从本质上讲，我的表是某些百分比的状态细分，我正在尝试将其上传到我的仪表板中。

import base64
import datetime
import io
import dash
from dash.dependencies import Input, Output, State
import dash_core_components as dcc
import dash_html_components as html
import dash_table
import pandas as pd

external_stylesheets = ['https://codepen.io/chriddyp/pen/bWLwgP.css']
app = dash.Dash(__name__, external_stylesheets=external_stylesheets)
app.layout = html.Div([
    dcc.Upload(
        id='upload-data',
        children=html.Div([
            'Drag and Drop or ',
            html.A('Select Files')
        ]),
        style={
            'width': '100%',
            'height': '120px',
            'lineHeight': '60px',
            'borderWidth': '1px',
            'borderStyle': 'dashed',
            'borderRadius': '5px',
            'textAlign': 'center',
            'margin': '10px'
        },
        # Allow multiple files to be uploaded
        multiple=True
    ),
    html.Div(id='output-data-upload'),
])

def parse_contents(contents, filename, date):
    content_type, content_string = contents.split(',')
    decoded = base64.b64decode(content_string)
    try:
        if 'csv' in filename:
            # Assume that the user uploaded a CSV file
            df = pd.read_csv(
                io.StringIO(decoded.decode('utf-8')))
        elif 'xls' in filename:
            # Assume that the user uploaded an excel file
            df = pd.read_excel(io.BytesIO(decoded))
    except Exception as e:
        print(e)
        return html.Div([
            'There was an error processing this file.'
        ])
def generate_table(df, max_rows=10):
    return html.Table(
        # Header
        [html.Tr([html.Th(col) for col in df.columns])] +
        # Body
        [html.Tr([
            html.Td(df.iloc[i][col]) for col in df.columns
        ]) for i in range(min(len(df), max_rows))]
    )
external_stylesheets = ['https://codepen.io/chriddyp/pen/bWLwgP.css']
app = dash.Dash(__name__, external_stylesheets=external_stylesheets)
app.layout = html.Div(children =[
    html.H4(children = 'test'),
    dcc.Dropdown( id = 'dropdown', options = [
        {'label' : i , 'value' : i} for i in df.state.unique()
    ],  multi = True, placeholder = 'Filter by State'),
    html.Div(id='table-container'),
        ])

def display_table(dropdown_value):
    if dropdown_value is None:
        return generate_table(df)

    #x = df[df['state'] == str(dropdown_value)]
    return html.Div([
        html.H5(filename),
        html.H6(datetime.datetime.fromtimestamp(date)),
        generate_table(df[df['state'].isin(dropdown_value)])
#app.css.append_css({"external_url": "https://codepen.io/chriddyp/pen/bWLwgP.css"})

@app.callback(
    dash.dependencies.Output('table-container', 'children'),
    [dash.dependencies.Input('dropdown','value')])

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

Answer 1

嗨@ntwong我建议使用 dash_tables 来显示数据帧，这是您最接近的数据帧。 以下是一些使其正常工作的基本代码：

import dash_table
import pandas as pd
import dash_html_components as html
# create your dataframe "df" from your data idk what method you are using
    html.Div([
       dash_table.DataTable(data=df.to_dict("rows"), columns = [{"id": x, "name": x} for x in df.columns])
    ])

只需将代码放在脚本正文中即可。

Answer 2

不鼓励渲染原始 HTML，这里的其他人已经描述了将解析的 html 转换为dash-html-components以与dash_table一起使用的函数。您可以通过提供正确的样式信息使表格"看起来像"本机 jupyter 中的表格 - 或者您可以下载破折号危险设置内部 html 包，它可以让你显示它。

一个问题是，当你做df.to_html()时，pandas 只返回一个基本的 html，而不是像这个问题中那样带有任何样式属性的 html——你可以通过渲染 df 然后获取 html 来解决(见下文(。 然后你解析 html，将样式提取到样式字典中。然后，也许您可以使用style_table/style_cell属性将这些样式传递给dash_table。

html = (df.style.render())

查看本指南，了解有关构建表的更多信息，