Trying to display all y-axis names in scatter chart even without data

[AIMPED]

Hi @ShreyanshG,

while @AbdelAnlah has a valid point, you could map your names to integers, plot these integers on the y-axis over the x-axis and use custom ticks to use the actual names. You could also map a color to each name.

import pandas as pd
import random
import plotly.express as px

random.seed(42)
days = 31

# create data
week = pd.date_range('01/01/2022', periods=days, freq='D')

# all names
all_names = list('ABCDEFGHIJKLMNOPQRSTUVWXYZ')

# current names in period
current_names = list('EFGHIJKXRQD')
current_names = [random.choice(current_names) for _ in range(days)]

# name mapping name --> int
name_map_dict = {n: i for n, i in zip(all_names, range(len(all_names)))}

# color mapping name -- color string
color_map_dict = {n: c for n, c in zip(all_names, px.colors.qualitative.Alphabet)}


# create DataFrame
df  = pd.DataFrame({'date': week, 'names': current_names})

# add columns with mapped entities
df['name_mapped_to_int'] = df.names.apply(lambda x: name_map_dict[x])
df['name_mapped_to_color'] = df.names.apply(lambda x: color_map_dict[x])


# create figure
fig = px.scatter(df, x='date', y='name_mapped_to_int')

# custom range and ticks
fig.update_layout({
    'yaxis': {
        'range': [0, len(all_names)],
        'tickmode': 'array',
        'tickvals': [*range(len(all_names))],
        'ticktext': all_names
    },
    'height': 600,
    'width': 600,
    'template': 'plotly_dark'
})

fig.update_traces(marker_color=df.name_mapped_to_color)

creates: