Bitmask and flags - OLCI
Posted: Tue May 02, 2023 2:48 pm
Hi François, I hope you are doing well.
I am new to Python and to POLYMER. I am working on OLCI-Rrs validation in CASE 2 - inland waters, but I am having trouble understanding and applying the flags. I took a look at the common.py script to understand the value of each flag, but I do not understand where the value of 1023 for the BITMASK_REJECT in the params.py script is coming from:
# BITMASK
# (see common.py for bitmask definition)
# no product (NaN) in case of...
self.BITMASK_INVALID = 1+2+4+32+512
# recommended pixek rejection test: (bitmask & BITMASK_REJECT) != 0
self.BITMASK_REJECT = 1023
Furthermore, according to the script above, it says there is a recommended pixel rejection expression, but the parameter BITMASK_REJECT is not that expression, but a value. Could you please tell me if I need to modify the value of BITMASK_REJECT to set the expression? If yes, how can I modify it?
Thanks in advance,
Patricia
I am new to Python and to POLYMER. I am working on OLCI-Rrs validation in CASE 2 - inland waters, but I am having trouble understanding and applying the flags. I took a look at the common.py script to understand the value of each flag, but I do not understand where the value of 1023 for the BITMASK_REJECT in the params.py script is coming from:
# BITMASK
# (see common.py for bitmask definition)
# no product (NaN) in case of...
self.BITMASK_INVALID = 1+2+4+32+512
# recommended pixek rejection test: (bitmask & BITMASK_REJECT) != 0
self.BITMASK_REJECT = 1023
Furthermore, according to the script above, it says there is a recommended pixel rejection expression, but the parameter BITMASK_REJECT is not that expression, but a value. Could you please tell me if I need to modify the value of BITMASK_REJECT to set the expression? If yes, how can I modify it?
Thanks in advance,
Patricia