spacex_dash_app.py

# Import required libraries
import pandas as pd
import dash
import dash_html_components as html
import dash_core_components as dcc
from dash.dependencies import Input, Output
import plotly.express as px

# Read the airline data into pandas dataframe
spacex_df = pd.read_csv("spacex_launch_dash.csv")
max_payload = spacex_df['Payload Mass (kg)'].max()
min_payload = spacex_df['Payload Mass (kg)'].min()

# Create a dash application
app = dash.Dash(__name__)

# Create an app layout
app.layout = html.Div(children=[html.H1('SpaceX Launch Records Dashboard',
                                        style={'textAlign': 'center', 'color': '#503D36',
                                               'font-size': 40}),
                                # TASK 1: Add a dropdown list to enable Launch Site selection
                                # The default select value is for ALL sites
                                # dcc.Dropdown(id='site-dropdown',...)
                                dcc.Dropdown( id='site-dropdown', options=[
                                        { 'label':'All Sites','value':'ALL' },
                                        { 'label':'CCAFS LC-40','value':'CCAFS LC-40'},
                                        { 'label':'CCAFS SLC-40','value':'CCAFS SLC-40'},
                                        { 'label':'KSC LC-39A','value':'KSC LC-39A'},
                                        { 'label':'VAFB SLC-4E','value':'VAFB SLC-4E'}], 
                                        value='ALL',placeholder="Select a Launch Site Here", searchable=True ),
                                html.Br(),

                                # TASK 2: Add a pie chart to show the total successful launches count for all sites
                                # If a specific launch site was selected, show the Success vs. Failed counts for the site
                                html.Div(dcc.Graph(id='success-pie-chart')),
                                html.Br(),

                                html.P("Payload Range (Kg):"),
                                # TASK 3: Add a slider to select payload range
                                #dcc.RangeSlider(id='payload-slider',...)
                                dcc.RangeSlider( id='payload-slider',
                                                min=0,
                                                max=10000,
                                                step=1000,
                                                marks={ 
                                                        0:'0',
                                                        2500:'2500',
                                                        5000:'5000',
                                                        7500:'7500',
                                                        10000:'10000'
                                                        },
                                                value=[min_payload, max_payload]
                                                ),

                                # TASK 4: Add a scatter chart to show the correlation between payload and launch success
                                html.Div(dcc.Graph(id='success-payload-scatter-chart')),
                                ])

# TASK 2:
# Add a callback function for `site-dropdown` as input, `success-pie-chart` as output
@app.callback( Output( component_id='success-pie-chart', component_property='figure' ),
                Input( component_id='site-dropdown', component_property='value' ) )
def get_pie_chart(entered_site):
    filtered_df = spacex_df
    if entered_site == 'ALL':
        fig = px.pie( filtered_df, values='class', 
        names='Launch Site', 
        title='Success Count For All Launch Sites' )
        return fig
    else:
        f_data = filtered_df[ filtered_df['Launch Site']==entered_site ].groupby( ['class'] ).size().reset_index().rename( columns={0:'count'} )
        fig = px.pie( f_data,values='count',
        names = 'class',
        title = 'Success Count For {} Launch Site'.format(entered_site) )
        return fig

# TASK 4:
# Add a callback function for `site-dropdown` and `payload-slider` as inputs, `success-payload-scatter-chart` as output
@app.callback( Output( component_id='success-payload-scatter-chart', component_property='figure' ),
              [ Input( component_id='site-dropdown', component_property='value' ), 
                Input( component_id="payload-slider", component_property="value" ) ])
def get_scatter_chart(entered_site,payload_value):
    df_filt = spacex_df[(spacex_df['Payload Mass (kg)']>payload_value[0]) & (spacex_df['Payload Mass (kg)']<payload_value[1])]
    if entered_site == 'ALL':
        fig = px.scatter(df_filt,x='Payload Mass (kg)', y='class', 
        title='Correlation between Payload For All Launch Sites' )
        return fig
    else:
        df_filt = df_filt[ df_filt['Launch Site']==entered_site ]
        fig = px.scatter(df_filt,x='Payload Mass (kg)', y='class', 
        title = 'Correlation between Payload and {} Launch Site'.format(entered_site) )
        return fig
# Run the app
if __name__ == '__main__':
    app.run_server()