Hi,
I have been working on this problem for a while now. Essentially my code uploads a data set and they can choose certain dropdowns to populate a graph. I have now added a range slider to adjust the range of the colour bar - (which allows the user to remove outliers in their color scale). The range slider works fine HOWEVER it is using a range of [0,100] which is the default I am assuming? It does not pick up the ‘max’ and ‘min’ of the range slider that I have put in my code. I have printed these to double-check these values and they do provide the min and max of the selected drop-down component however these values do not correspond to the range slider. I am unsure about how to fix this and would, therefore, welcome any help if available. My code and respective data set is below:
Thank you
Best
Tilly
import base64
import io
from flask import Flask
import dash
from dash.dependencies import Input, Output, State
import dash_core_components as dcc
import dash_html_components as html
import plotly_express as px
import pandas as pd
external_stylesheets = ['https://codepen.io/chriddyp/pen/bWLwgP.css']
server = Flask(__name__)
app = dash.Dash(external_stylesheets=external_stylesheets, server=server)
app.layout = html.Div([dcc.Upload(
id='data-table-upload',
children=html.Div([html.Button('Upload File')],
style={'width': '49%', 'height': "60px", 'borderWidth': '1px',
'borderRadius': '5px',
'textAlign': 'center',
}),
multiple=False
),
html.Div([html.Div([html.Div([dcc.Graph(id='my-3D-graph', animate=False)], style={'display': 'inline-block',
'width': '74%',
}),
html.Div([
html.Div([html.Label(
["Select X variable:",
dcc.Dropdown(
id='xaxis-anim-3D',
multi=False,
placeholder="Select an "
"option "
"for X")],
)],
style={
'padding': 10}),
html.Div([html.Label(
["Select Y variable:",
dcc.Dropdown(
id='yaxis-anim-3D',
multi=False,
placeholder='Select an option '
'for Y')],
), ],
style={
'padding': 10}),
html.Div([html.Label(
["Select color variable:",
dcc.Dropdown(
id='caxis-anim-3D',
multi=False,
placeholder='Select an option for color')],
)], style={
'padding': 10}),
html.Div([
html.Label(["Select color bar "
"range:",
dcc.RangeSlider(
id='colorbar-slider',
), html.Div(id='slider-output-container')])
], style={'fontSize': 14,
'font-family': 'Arial',
'height': '20%',
'padding': 15,
})
],
style={
'display': 'inline-block',
'width': '25%',
'float': 'right',
'fontSize': 14,
'font-family': 'Arial',
'backgroundColor': '#ffffff'})
], className='container',
style={'padding': 40,
'backgroundColor': '#ffffff'})])
])
def parse_contents(contents, filename):
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))
elif 'txt' or 'tsv' in filename:
df = pd.read_csv(io.StringIO(decoded.decode('utf-8')), delimiter=r'\s+'
)
except Exception as e:
print(e)
return html.Div([
'There was an error processing this file.'
])
return df
# POPULATE X AXIS DROPDOWN
@app.callback(Output('xaxis-anim-3D', 'options'),
[Input('data-table-upload', 'contents')],
[State('data-table-upload', 'filename')])
def populate_xaxis_dropdown_anim(contents, filename):
df = parse_contents(contents, filename)
return [{'label': i, 'value': i} for i in df.columns]
# POPULATE Y AXIS DROPDOWN
@app.callback(Output('yaxis-anim-3D', 'options'),
[Input('data-table-upload', 'contents')],
[State('data-table-upload', 'filename')])
def populate_yaxis_dropdown_anim(contents, filename):
df = parse_contents(contents, filename)
return [{'label': i, 'value': i} for i in df.columns]
# POPULATE C AXIS DROPDOWN
@app.callback(Output('caxis-anim-3D', 'options'),
[Input('data-table-upload', 'contents')],
[State('data-table-upload', 'filename')])
def populate_saxis_dropdown_anim(contents, filename):
df = parse_contents(contents, filename)
return [{'label': i, 'value': i} for i in df.columns]
# POPULATE COLORBAR SLIDER SCATTER
@app.callback([Output('colorbar-slider', 'min'),
Output('colorbar-slider', 'max'),
Output('colorbar-slider', 'step')
],
[Input('data-table-upload', 'contents'),
Input('caxis-anim-3D', 'value')
],
[State('data-table-upload', 'filename')])
def populate_pressure_slider(contents, color, filename):
df = parse_contents(contents, filename)
min = round(int(df[color].min())),
max = round(int(df[color].max())),
step = 0.5
return min, max, step
@app.callback(
Output('slider-output-container', 'children'),
[Input('colorbar-slider', 'value')]
)
def update_output(value):
return 'You have selected "{}"'.format(value)
@app.callback(Output('my-3D-graph', 'figure'),
[Input('data-table-upload', 'contents'),
Input('xaxis-anim-3D', 'value'),
Input('yaxis-anim-3D', 'value'),
Input('caxis-anim-3D', 'value'),
Input('colorbar-slider', 'value'),
],
[State('data-table-upload', 'filename')]
)
def update_figure(contents, x, y, color, color_value, filename):
df = parse_contents(contents, filename)
color_val_float = []
for i in range(0, len(color_value), 1):
color_val_float.append(float(color_value[i]))
color_val = color_val_float
print(color_val)
return px.scatter(df, x=df[x], y=df[y], title="", animation_frame="Pressure",
animation_group=df.columns[0],
hover_name=df.columns[0],
hover_data={}, template="none", color=df[color],
color_continuous_scale='Viridis', range_color=color_val
).update_xaxes(showgrid=False, title=x, autorange=True, ticks='outside',
showline=True, showspikes=True, spikethickness=1, spikedash='solid',
mirror=True, tickformat=".1f").update_yaxes(spikedash='solid',
showgrid=False,
title=dict(text=y,
standoff=5),
autorange=True, ticks='outside',
showspikes=True, spikethickness=1,
showline=True, mirror=True,
tickformat=".1f").update_layout(
clickmode='event+select', hovermode='closest', margin={'l': 80}, autosize=True, font=dict(family='Helvetica',
),
coloraxis_colorbar=dict(title=dict(text=color, side='right'), ypad=0),
).update_traces(marker=dict(size=10,
opacity=0.7,
showscale=False,
line=dict(width=0.7, color='DarkSlateGrey'),
colorscale="Viridis"))
if __name__ == '__main__':
app.run_server()
DATASET USED:
Thank you!
