Time-series covariance conversion

[jchencyz]

Based on error propagation, I suppose that converting the time-series covariance from phase to range requires squaring the conversion factor (i.e., (np.abs(phase2range))²)

Full script that generated the error

In ifgram_inversion.py:

ts = ts.reshape(num_date, num_row, num_col)
    ts_cov = ts_cov.reshape(num_date, num_date, num_row, num_col) if calc_cov else ts_cov
    inv_quality = inv_quality.reshape(num_row, num_col)
    num_inv_obs = num_inv_obs.reshape(num_row, num_col)

    # 3.2 convert displacement unit to meter
    if obs_ds_name.startswith(('unwrapPhase','ion')):
        phase2range = -1 * float(stack_obj.metadata['WAVELENGTH']) / (4.*np.pi)
        ts *= phase2range
        ts_cov = ts_cov * np.abs(phase2range) if calc_cov else ts_cov
        print('converting LOS phase unit from radian to meter')

Full error message

N/A

System information

• Operating system:
• Python environment:
• MintPy version:
• InSAR processor/product:
• Your custom / default template file (if the bug is related to a specific dataset):

[welcome[bot]]

👋 Thanks for opening your first issue here! Please filled out the template with as much details as possible. We appreciate that you took the time to contribute! Make sure you read our contributing guidelines.