dash IBM week 4 exercise

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

# Read the airline data into pandas dataframe
airline_data =  pd.read_csv('https://cf-courses-data.s3.us.cloud-object-storage.appdomain.cloud/IBMDeveloperSkillsNetwork-DV0101EN-SkillsNetwork/Data%20Files/airline_data.csv', 
                            encoding = "ISO-8859-1",
                            dtype={'Div1Airport': str, 'Div1TailNum': str, 
                                   'Div2Airport': str, 'Div2TailNum': str})
# Create a dash application
app = dash.Dash(__name__)

# Get the layout of the application and adjust it.
# Create an outer division using html.Div and add title to the dashboard using html.H1 component
# Add a html.Div and core input text component
# Finally, add graph component.
app.layout = html.Div(children=[html.H1(children='Airline Performance Dashboard', style={'textAlign' : 'center', 'color':'#503D36', 'font-size':40 }),
                                html.Div(["Input Year", dcc.Input(id="input-year", value=2010, type="number", style={'marginRight':'50px','font-size':35}),], 
                                style={'font-size':40}),
                                html.Br(),
                                html.Br(),
                                html.Div(dcc.Graph(id="line-plot")),
                                ])


# add callback decorator
@app.callback(Output(component_id= "line-plot", component_property='figure'),
               Input(component_id= "input-year", component_property='value'))

# Add computation to callback function and return graph
def get_graph(entered_year):
    # Select data based on the entered year
    df =  airline_data[airline_data['Year']==int(entered_year)]

    # Group the data by Month and compute average over arrival delay time.
    line_data = df.groupby('Month')['ArrDelay'].mean().reset_index()

    # 
    fig = go.Figure(data=go.Scatter(x=line_data['Month'], y=line_data['ArrDelay'], mode='lines', marker=dict(color='green')))
    fig.update_layout(title='Month vs Average Flight Delay Time',xaxis_title='month',yaxis_title='Arrdelay')
    return fig

# Run the app
if __name__ == '__main__':
    app.run_server()