GPX analysis - step 4

GPX_analysis_step_4.py

# Create a column with values that are 'shifted' one forwards, so we can create calculations for differences.
df['lon-start'] = df['lon']
df['lon-start'].iloc[-1] = np.nan
df['lon-start'] = np.roll(df['lon-start'], 1)
df['lat-start'] = df['lat']
df['lat-start'].iloc[-1] = np.nan
df['lat-start'] = np.roll(df['lat-start'], 1)
df['alt-start'] = df['alt']
df['alt-start'].iloc[-1] = np.nan
df['alt-start'] = np.roll(df['alt-start'], 1)
df['time-start'] = df['time']
df['time-start'].iloc[-1] = np.nan
df['time-start'] = np.roll(df['time-start'], 1)
df = df.fillna(method='bfill')