replace removed Styler.applymap with Styler.map

[PradeepJaiswar]

Fix: Styler.applymap removed in pandas 3.0

Problem

Opening the Portfolio & Streaming → Sector Index Comparison example in the interactive Streamlit app crashes with:

AttributeError: 'Styler' object has no attribute 'applymap'
  File "interactive_examples/streamlit_app.py", line 1503, in <module>
    st.dataframe(df.style.applymap(color_chg, subset=["Change", "Change %"]), ...)

pandas.io.formats.style.Styler.applymap was deprecated in pandas 2.1.0 and removed in pandas 3.0. Since
interactive_examples/requirements.txt pins no upper bound on pandas, users on a current pandas pick up 3.x and hit the
crash.

Fix

Rename the two elementwise-styling calls from .style.applymap(...) to .style.map(...). Styler.map is the direct
replacement with an identical signature (func, subset=), so this is a pure rename with no behavior change.

Affected lines in interactive_examples/streamlit_app.py:

• Line 1503 — Sector Index Comparison (color Change / Change % cells)
• Line 1802 — status coloring example