ValueError: band_id already exists as coordinate or variable name. Xarray concat Error

I have 2 different x-array dataset like shown below:

<xarray.Dataset>  Dimensions:                                           (band: 1, num_star_looks: 24, number_of_image_bounds: 2, number_of_time_bounds: 2, x: 10848, y: 10848)  Coordinates:      t                                                 datetime64[ns] ...    * y                                                 (y) float32 0.151858 ... -0.151858    * x                                                 (x) float32 -0.151858 ... 0.151858      band_id                                           (band) int8 1      band_wavelength                                   (band) float32 ...  Dimensions without coordinates: band, num_star_looks, number_of_image_bounds, number_of_time_bounds  Data variables:      Rad                                               (y, x) float32 ...  

2nd dataset:

<xarray.Dataset>  Dimensions:                                           (band: 1, num_star_looks: 24, number_of_image_bounds: 2, number_of_time_bounds: 2, x: 10848, y: 10848)  Coordinates:      t                                                 datetime64[ns] ...    * y                                                 (y) float32 0.151858 ... -0.151858    * x                                                 (x) float32 -0.151858 ... 0.151858      band_id                                           (band) int8 2      band_wavelength                                   (band) float32 ...  Dimensions without coordinates: band, num_star_looks, number_of_image_bounds, number_of_time_bounds  Data variables:      Rad                                               (y, x) float32 ...  

Both have different values in coordinate t and band_id. Now I want to concat them using band_id dim, but I'm getting error as:

xr.concat([F1, F2], dim = 'band_id')    

ValueError: band_id already exists as coordinate or variable name.    

When I try to concat it using dimension t it's working perfectly as I wanted and resulting following array.

<xarray.Dataset>  Dimensions:                                           (band: 1, num_star_looks: 24, number_of_image_bounds: 2, number_of_time_bounds: 2, t: 2, x: 10848, y: 10848)  Coordinates:      band_id                                           (band) int8 1    * y                                                 (y) float32 0.151858 ... -0.151858    * x                                                 (x) float32 -0.151858 ... 0.151858    * t                                                 (t) datetime64[ns] 2019-04-10T00:05:08.113467008 2019-04-11T00:05:06.598942080  Dimensions without coordinates: band, num_star_looks, number_of_image_bounds, number_of_time_bounds  Data variables:      Rad                                               (t, y, x) float32 ...  

I want something similar dimension in Rad variable but instead of t I want band_id.

What I think is maybe there's dimension ````bandinband_idcoordinate and there's no dimension int``` so it's working there.

from Recent Questions - Stack Overflow https://stackoverflow.com/questions/65376927/valueerror-band-id-already-exists-as-coordinate-or-variable-name-xarray-concat Chris_007