Update app.py

app.py

@@ -1,4 +1,3 @@
-
 import streamlit as st
 import pandas as pd
 import altair as alt
@@ -26,40 +25,45 @@ def convert_population(value):
 population.iloc[:, 1:] = population.iloc[:, 1:].applymap(convert_population)
 
 # Streamlit app title
-st.title("Child Mortality vs Population Across Years")
-
-# Sidebar: Year selection
-year = st.sidebar.slider("Select Year", min_value=1800, max_value=2020, value=2020, step=1)
-
-# Filter datasets for the selected year
-mortality_year = child_mortality[['country', str(year)]].rename(columns={str(year): 'child_mortality'})
-population_year = population[['country', str(year)]].rename(columns={str(year): 'population'})
-
-# Merge datasets
-merged_data = pd.merge(mortality_year, population_year, on='country', how='inner').dropna()
+st.title("Country Trends: Child Mortality and Population Over Time")
 
-# Sidebar: Country dropdown
-countries = ['All'] + sorted(merged_data['country'].unique())
+# Sidebar: Country selection
+countries = sorted(child_mortality['country'].unique())
 selected_country = st.sidebar.selectbox("Select Country", countries)
 
-if selected_country != 'All':
-    merged_data = merged_data[merged_data['country'] == selected_country]
+# Filter datasets for the selected country
+if selected_country:
+    mortality_country = child_mortality[child_mortality['country'] == selected_country].melt(
+        id_vars='country', var_name='year', value_name='child_mortality'
+    )
+    population_country = population[population['country'] == selected_country].melt(
+        id_vars='country', var_name='year', value_name='population'
+    )
 
-# Scatter plot
-scatter_chart = alt.Chart(merged_data).mark_circle(size=60).encode(
-    x=alt.X('population', title='Population'),
-    y=alt.Y('child_mortality', title='Child Mortality Rate'),
-    tooltip=['country', 'population', 'child_mortality']
-).properties(
-    width=700,
-    height=400,
-    title=f"Child Mortality vs Population in {year}"
-)
+    # Merge datasets
+    merged_country_data = pd.merge(mortality_country, population_country, on=['country', 'year'], how='inner')
+    merged_country_data['year'] = merged_country_data['year'].astype(int)
 
-# Display chart
-st.altair_chart(scatter_chart, use_container_width=True)
+    # Line chart for trends
+    line_chart = alt.Chart(merged_country_data).transform_fold(
+        fold=['child_mortality', 'population'],
+        as_=['Metric', 'Value']
+    ).mark_line().encode(
+        x=alt.X('year:O', title='Year'),
+        y=alt.Y('Value:Q', title='Value', scale=alt.Scale(type='log')),
+        color=alt.Color('Metric:N', title='Metric'),
+        tooltip=['year', 'child_mortality', 'population']
+    ).properties(
+        width=700,
+        height=400,
+        title=f"Trends in Child Mortality and Population for {selected_country}"
+    )
 
-# Data preview
-st.subheader("Data Preview")
-st.write(merged_data)
+    # Display chart
+    st.altair_chart(line_chart, use_container_width=True)
 
+    # Data preview
+    st.subheader("Data Preview")
+    st.write(merged_country_data)
+else:
+    st.warning("Please select a country to view the trends.")