Implement Streamlit UI for Boltzmann wealth model (#36)

* Implement Streamlit UI for Boltzmann wealth model

* change slider text

* change slider text

* update readme

---------

Co-authored-by: Ankit Kumar <ankit.kumar@tum.de>

Author: ankitk50

Readme.md

@@ -33,6 +33,12 @@ If your browser doesn't open automatically, point it to [http://127.0.0.1:8521/]
 * ``boltzmann_wealth_model/server.py``: Code for the interactive visualization.
 * ``run.py``: Launches the server.
 
+## Optional
+
+*  ``boltzmann_wealth_model/app.py``: can be used to run the simulation via the streamlit interface.
+* For this some additional packages like ``streamlit`` and ``altair`` needs to be installed.
+* Once installed, the app can be opened in the browser using : ``streamlit run app.py``
+
 ## Further Reading
 
 The full tutorial describing how the model is built can be found at:

app.py

@@ -0,0 +1,117 @@
+from boltzmann_wealth_model.model import BoltzmannWealthModel
+
+import streamlit as st
+
+import time
+
+import pandas as pd
+
+import altair as alt
+
+
+model = st.title("Boltzman Wealth Model")
+num_agents = st.slider(
+    "Choose how many agents to include in the model",
+    min_value=1,
+    max_value=100,
+    value=50,
+)
+num_ticks = st.slider(
+    "Select number of Simulation Runs", min_value=1, max_value=100, value=50
+)
+height = st.slider("Select Grid Height", min_value=10, max_value=100, step=10, value=15)
+width = st.slider("Select Grid Width", min_value=10, max_value=100, step=10, value=20)
+model = BoltzmannWealthModel(num_agents, height, width)
+
+
+status_text = st.empty()
+run = st.button("Run Simulation")
+
+
+if run:
+    tick = time.time()
+    step = 0
+    # init grid
+    df_grid = pd.DataFrame()
+    df_gini = pd.DataFrame({"step": [0], "gini": [-1]})
+    for x in range(width):
+        for y in range(height):
+            df_grid = pd.concat(
+                [df_grid, pd.DataFrame({"x": [x], "y": [y], "agent_count": 0})],
+                ignore_index=True,
+            )
+
+    heatmap = (
+        alt.Chart(df_grid)
+        .mark_point(size=100)
+        .encode(x="x", y="y", color=alt.Color("agent_count"))
+        .interactive()
+        .properties(width=800, height=600)
+    )
+
+    line = (
+        alt.Chart(df_gini)
+        .mark_line(point=True)
+        .encode(x="step", y="gini")
+        .properties(width=800, height=600)
+    )
+
+    # init progress bar
+    my_bar = st.progress(0, text="Simulation Progress")  # progress
+    placeholder = st.empty()
+    st.subheader("Agent Grid")
+    chart = st.altair_chart(heatmap)
+    st.subheader("Gini Values")
+    line_chart = st.altair_chart(line)
+
+    color_scale = alt.Scale(
+        domain=[0, 1, 2, 3, 4], range=["red", "cyan", "white", "white", "blue"]
+    )
+    for i in range(num_ticks):
+        model.step()
+        my_bar.progress((i / num_ticks), text="Simulation progress")
+        placeholder.text("Step = %d" % i)
+        for cell in model.grid.coord_iter():
+            cell_content, x, y = cell
+            agent_count = len(cell_content)
+            selected_row = df_grid[(df_grid["x"] == x) & (df_grid["y"] == y)]
+            df_grid.loc[
+                selected_row.index, "agent_count"
+            ] = agent_count  # random.choice([1,2])
+
+        df_gini = pd.concat(
+            [
+                df_gini,
+                pd.DataFrame(
+                    {"step": [i], "gini": [model.datacollector.model_vars["Gini"][i]]}
+                ),
+            ]
+        )
+        # st.table(df_grid)
+        heatmap = (
+            alt.Chart(df_grid)
+            .mark_circle(size=100)
+            .encode(x="x", y="y", color=alt.Color("agent_count", scale=color_scale))
+            .interactive()
+            .properties(width=800, height=600)
+        )
+        chart.altair_chart(heatmap)
+
+        line = (
+            alt.Chart(df_gini)
+            .mark_line(point=True)
+            .encode(x="step", y="gini")
+            .properties(width=800, height=600)
+        )
+        line_chart.altair_chart(line)
+
+        time.sleep(0.01)
+
+    tock = time.time()
+    st.success(f"Simulation completed in {tock - tick:.2f} secs")
+
+    # st.subheader('Agent Grid')
+    # fig = px.imshow(agent_counts,labels={'color':'Agent Count'})
+    # st.plotly_chart(fig)
+    # st.subheader('Gini value over sim ticks (Plotly)')
+    # chart = st.line_chart(model.datacollector.model_vars['Gini'])