plot.py

import pandas as pd
import plotly.express as px
import geopandas as gpd
from shapely.geometry import Point

points_of_interest_newport_df = pd.read_csv(r"/Users/chloemurrell/DSST - Public Transport Efficiency/points-of-interest-newport-csv.csv", delimiter="|", dtype={"POINTX_CLASSIFICATION_CODE":str})

def clean_points_of_interest_df(df_in):

  # Select relevant columns
  df_clean = points_of_interest_newport_df[["NAME", "FEATURE_EASTING", "FEATURE_NORTHING"]]
  # Rename "NAME" column 
  df_clean = df_clean.rename(columns={"NAME":"id"})

  return df_clean

newport_locations_df = clean_points_of_interest_df(points_of_interest_newport_df)

def convert_coordinates(df_in, coord_col_1, coord_col_2):

  # Convert northing and easting -> longnitude and latitude
  geometry = [Point(xy) for xy in zip(df_in[coord_col_1], df_in[coord_col_2])]

  geo_df = gpd.GeoDataFrame(df_in, geometry=geometry)

  geo_df.crs = "EPSG:27700"
  
  geo_df.to_crs("EPSG:4326", inplace=True)

  # Extract lng and lat coodinates into separate columns from POINT() column. 
  geo_df['lng'] = geo_df['geometry'].x
  geo_df['lat'] = geo_df['geometry'].y

  # Convert to pandas df
  pd_df = pd.DataFrame(df_in)

  # Drop unnecessary columns
  pd_df = pd_df.drop([coord_col_1, coord_col_2, "geometry"], axis=1)

  # Rename longnitude column in line with API requirements - delete
  pd_df = pd_df.rename(columns={"lon":"lng"})

  # Add number to end of duplicate id  values
  mask = pd_df['id'].duplicated()
  pd_df.loc[mask, 'id'] += pd_df.groupby('id').cumcount().add(1).astype(str)

  # Drop na values - this occurs do to error in the original spreadsheet which needs fixing
  pd_df = pd_df.dropna(axis=0) 
                            
  return pd_df

newport_locations_df = convert_coordinates(newport_locations_df, "FEATURE_EASTING", "FEATURE_NORTHING")

fig = px.scatter_mapbox(
    newport_locations_df,  # Our DataFrame
    lat = "lat",
    lon = "lng",
    center = {"lat": 51.586106, "lon": -2.991391},  # where map will be centered
    width = 1500,  # Width of map
    height = 1500,  # Height of map
    hover_data = ["id"],  # what to display when hovering mouse over coordinate
)

fig.update_layout(mapbox_style="open-street-map") # adding beautiful street layout to map

fig.show()