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Adding N annotations takes O(N^2) time

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#5,316 1 comment 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
python

Research direction

Start by running the reproduction in the issue and profiling the repeated fig.add_annotation calls. Trace the Python Figure annotation path to identify where the cumulative cost grows, then verify that adding many annotations no longer shows quadratic behavior using the same script.

Written by the indexing model from the issue text.

Description

bug P2 performance

Plotly is unreasonably slow to add more than a few hundred annotations to a plot. This code

import time

import plotly


fig = plotly.graph_objects.Figure()

NUM_ANNOTATIONS=1000

start_time = time.monotonic()
for i in range(NUM_ANNOTATIONS):
    fig.add_annotation(
        x=i,
        y=time.monotonic() - start_time,
        text=str(i),
    )
    print(i)
fig.update_layout(
    xaxis_range=[0,NUM_ANNOTATIONS],
    yaxis_range=[0,time.monotonic() - start_time],
    xaxis_title_text="# Annotations",
    yaxis_title_text="Cumulative Time [s]",
)
fig.show()

produces this plot

Image
Dominant language
Python
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Avg merge
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Merged PRs (30d)
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