我试图重新创建下面显示在网络上的示例Towards Data Science Example
我编写了以下代码，对此进行了修改：
import dash
import dash_core_components as dcc
import dash_html_components as html
from dash.dependencies import Input, Output
import pandas as pd
import plotly.graph_objs as go
# Step 1. Launch the application
app = dash.Dash()
# Step 2. Import the dataset
filepath = 'https://raw.githubusercontent.com/plotly/datasets/master/finance-charts-apple.csv'
st = pd.read_csv(filepath)
# range slider options
st['Date'] = pd.to_datetime(st.Date)
dates = ['2015-02-17', '2015-05-17', '2015-08-17', '2015-11-17',
'2016-02-17', '2016-05-17', '2016-08-17', '2016-11-17', '2017-02-17']
features = st.columns[1:-1]
opts = [{'label' : i, 'value' : i} for i in features]
# Step 3. Create a plotly figure
trace_1 = go.Scatter(x = st.Date, y = st['AAPL.High'],
name = 'AAPL HIGH',
line = dict(width = 2,
color = 'rgb(229, 151, 50)'))
layout = go.Layout(title = 'Time Series Plot',
hovermode = 'closest')
fig = go.Figure(data = [trace_1], layout = layout)
# Step 4. Create a Dash layout
app.layout = html.Div([
# a header and a paragraph
html.Div([
html.H1("This is a Test Dashboard"),
html.P("Dash is great!!")
],
style = {'padding' : '50px' ,
'backgroundColor' : '#3aaab2'}),
# adding a plot
dcc.Graph(id = 'plot', figure = fig),
# dropdown
html.P([
html.Label("Choose a feature"),
dcc.Dropdown(
id='opt',
options=opts,
value=features[0],
multi=True
),
# range slider
html.P([
html.Label("Time Period"),
dcc.RangeSlider(id = 'slider',
marks = {i : dates[i] for i in range(0, 9)},
min = 0,
max = 8,
value = [1, 7])
], style = {'width' : '80%',
'fontSize' : '20px',
'padding-left' : '100px',
'display': 'inline-block'})
])
])
# Step 5. Add callback functions
@app.callback(Output('plot', 'figure'),
[Input('opt', 'value'),
Input('slider', 'value')])
def update_figure(input1, input2):
# filtering the data
st2 = st[(st.Date > dates[input2[0]]) & (st.Date < dates[input2[1]])]
# updating the plot
trace_1 = go.Scatter(x = st2.Date, y = st2['AAPL.High'],
name = 'AAPL HIGH',
line = dict(width = 2,
color = 'rgb(229, 151, 50)'))
trace_2 = go.Scatter(x = st2.Date, y = st2[input1],
name = input1,
line = dict(width = 2,
color = 'rgb(106, 181, 135)'))
fig = go.Figure(data = [trace_1, trace_2], layout = layout)
return fig
# Step 6. Add the server clause
if __name__ == '__main__':
app.run_server(debug = True)
它运行并初始化一切正常，直到我在下拉菜单中更改输入为止。生成了一个回调错误，我不知道它来自哪里。
该应用程序在本地运行，并在所有列中均显示了下拉菜单，更改了该下拉菜单的输入就产生了问题。
错误如下：
ValueError:
Invalid value of type 'builtins.list' received for the 'name' property of scatter
Received value: ['AAPL.Open', 'AAPL.Close']
The 'name' property is a string and must be specified as:
- A string
- A number that will be converted to a string
Traceback (most recent call last):
File "C:\test\Anaconda\lib\site-packages\flask\app.py", line 2309, in __call__
return self.wsgi_app(environ, start_response)
File "C:\test\Anaconda\lib\site-packages\flask\app.py", line 2295, in wsgi_app
response = self.handle_exception(e)
File "C:\test\Anaconda\lib\site-packages\flask\app.py", line 1741, in handle_exception
reraise(exc_type, exc_value, tb)
File "C:\test\Anaconda\lib\site-packages\flask\_compat.py", line 35, in reraise
raise value
File "C:\test\Anaconda\lib\site-packages\flask\app.py", line 2292, in wsgi_app
response = self.full_dispatch_request()
File "C:\test\Anaconda\lib\site-packages\flask\app.py", line 1815, in full_dispatch_request
rv = self.handle_user_exception(e)
File "C:\test\Anaconda\lib\site-packages\flask\app.py", line 1718, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "C:\test\Anaconda\lib\site-packages\flask\_compat.py", line 35, in reraise
raise value
File "C:\test\Anaconda\lib\site-packages\flask\app.py", line 1813, in full_dispatch_request
rv = self.dispatch_request()
File "C:\test\Anaconda\lib\site-packages\flask\app.py", line 1799, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "C:\test\Anaconda\lib\site-packages\dash\dash.py", line 1152, in dispatch
response.set_data(self.callback_map[output]['callback'](*args))
File "C:\test\Anaconda\lib\site-packages\dash\dash.py", line 1038, in add_context
output_value = func(*args, **kwargs)
File "C:\Users\Dash\Dash\test.py", line 87, in update_figure
color = 'rgb(106, 181, 135)'))
File "C:\test\Anaconda\lib\site-packages\plotly\graph_objs\__init__.py", line 37455, in __init__
self['name'] = name if name is not None else _v
File "C:\test\Anaconda\lib\site-packages\plotly\basedatatypes.py", line 3166, in __setitem__
self._set_prop(prop, value)
File "C:\test\Anaconda\lib\site-packages\plotly\basedatatypes.py", line 3407, in _set_prop
raise err
File "C:\test\Anaconda\lib\site-packages\plotly\basedatatypes.py", line 3402, in _set_prop
val = validator.validate_coerce(val)
File "C:\test\Anaconda\lib\site-packages\_plotly_utils\basevalidators.py", line 1005, in validate_coerce
self.raise_invalid_val(v)
File "C:\test\Anaconda\lib\site-packages\_plotly_utils\basevalidators.py", line 277, in raise_invalid_val
valid_clr_desc=self.description()))
ValueError:
Invalid value of type 'builtins.list' received for the 'name' property of scatter
Received value: ['AAPL.Open', 'AAPL.Close']
The 'name' property is a string and must be specified as:
- A string
- A number that will be converted to a string
答案 0 :(得分：1)
工作代码
您的错误出现在第85行。您只能将字符串或数字传递给name属性。我刚刚添加了pythons str()函数来将input1转换为字符串。 ：）
import dash
import dash_core_components as dcc
import dash_html_components as html
from dash.dependencies import Input, Output
import pandas as pd
import plotly.graph_objs as go
# Step 1. Launch the application
app = dash.Dash()
# Step 2. Import the dataset
filepath = 'https://raw.githubusercontent.com/plotly/datasets/master/finance-charts-apple.csv'
st = pd.read_csv(filepath)
# range slider options
st['Date'] = pd.to_datetime(st.Date)
dates = ['2015-02-17', '2015-05-17', '2015-08-17', '2015-11-17',
'2016-02-17', '2016-05-17', '2016-08-17', '2016-11-17', '2017-02-17']
features = st.columns[1:-1]
opts = [{'label' : i, 'value' : i} for i in features]
# Step 3. Create a plotly figure
trace_1 = go.Scatter(x = st.Date, y = st['AAPL.High'],
name = 'AAPL HIGH',
line = dict(width = 2,
color = 'rgb(229, 151, 50)'))
layout = go.Layout(title = 'Time Series Plot',
hovermode = 'closest')
fig = go.Figure(data = [trace_1], layout = layout)
# Step 4. Create a Dash layout
app.layout = html.Div([
# a header and a paragraph
html.Div([
html.H1("This is a Test Dashboard"),
html.P("Dash is great!!")
],
style = {'padding' : '50px' ,
'backgroundColor' : '#3aaab2'}),
# adding a plot
dcc.Graph(id = 'plot', figure = fig),
# dropdown
html.P([
html.Label("Choose a feature"),
dcc.Dropdown(
id='opt',
options=opts,
value=features[0],
multi=True
),
# range slider
html.P([
html.Label("Time Period"),
dcc.RangeSlider(id = 'slider',
marks = {i : dates[i] for i in range(0, 9)},
min = 0,
max = 8,
value = [1, 7])
], style = {'width' : '80%',
'fontSize' : '20px',
'padding-left' : '100px',
'display': 'inline-block'})
])
])
# Step 5. Add callback functions
@app.callback(Output('plot', 'figure'),
[Input('opt', 'value'),
Input('slider', 'value')])
def update_figure(input1, input2):
# filtering the data
st2 = st[(st.Date > dates[input2[0]]) & (st.Date < dates[input2[1]])]
# updating the plot
trace_1 = go.Scatter(x = st2.Date, y = st2['AAPL.High'],
name = 'AAPL HIGH',
line = dict(width = 2,
color = 'rgb(229, 151, 50)'))
trace_2 = go.Scatter(x = st2.Date, y = st2[input1],
name = str(input1),
line = dict(width = 2,
color = 'rgb(106, 181, 135)'))
fig = go.Figure(data = [trace_1, trace_2], layout = layout)
return fig
# Step 6. Add the server clause
if __name__ == '__main__':
app.run_server(debug = True)
答案 1 :(得分：0)
回调错误快速修复
在callback上收到类似的错误。简单的dash更新就解决了。
pip install dash --upgrade