Add Markers in Viz for particular values for column in plotly

Question

I am trying to add marker's in scatter plot if [df['signals1'] == -1] in ploltly.But the markers are not getting added.

df['signals1'].head(10)

Date        Signals
2021-06-04   -1
2021-06-07   -1
2021-06-08   -1
2021-06-09   -1
2021-06-10   -1
2021-06-11   -1
2021-06-14   -1
2021-06-15   -1
2021-06-16   -1
2021-06-17   -1

Current Viz-

Code-

fig = go.Figure(data = [ 
              go.Scatter(x=df.index, y=[df['signals1'] == -1], mode = 'markers',
              marker =dict(symbol='triangle-down', size = 16),
              name='Flag')])

In matplotlib, below code is working fine.

u1, = bx.plot(df['Close'][df['signals1'] == -1], lw=0, marker='^', markersize=8, c='g',alpha=0.7)

Ref link -https://medium.com/analytics-vidhya/statistical-arbitrage-with-pairs-trading-and-backtesting-ec657b25a368

Answer 1

The reason why the signal values could not be drawn is that the column names in the data and the column names used in the graph differ in case. Besides, the signal value is a negative value, so the current y-axis is a price, so a price must be specified. So I am modifying the data presented to fit the code.

import plotly.express as px
import plotly.graph_objects as go
import pandas as pd
import io

data = '''
Date        Signals
2015-03-04   133
2015-04-07   125
2015-05-08   145
2016-03-04   133
2016-04-07   125
2016-05-08   145
2017-03-04   133
2017-04-07   125
2017-05-08   145
'''

df_s = pd.read_csv(io.StringIO(data), delim_whitespace=True)
df_s['Date'] = pd.to_datetime(df_s['Date'])
df_s.set_index('Date', inplace=True)

df = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/finance-charts-apple.csv')

fig = px.line(df, x='Date', y='AAPL.High', title='Time Series with Range Slider and Selectors')

fig.add_trace(go.Scatter(
    x=df_s.index,
    y=df_s['Signals'],
    mode = 'markers',
    marker =dict(symbol='triangle-down', size = 16),
    name='Flag'
)
             )

fig.update_xaxes(
    rangeslider_visible=True,
    rangeselector=dict(
        buttons=list([
            dict(count=1, label="1m", step="month", stepmode="backward"),
            dict(count=6, label="6m", step="month", stepmode="backward"),
            dict(count=1, label="YTD", step="year", stepmode="todate"),
            dict(count=1, label="1y", step="year", stepmode="backward"),
            dict(step="all")
        ])
    )
)
# update
fig.update_layout(template='plotly_dark',
                  xaxis_rangeselector_font_color='black',
                  xaxis_rangeselector_activecolor='red',
                  xaxis_rangeselector_bgcolor='green',
                 )
fig.show()