How to replace very small value with 0 in MEGANv3.2 result with ioapi library

MEGAN
8

Thanks for posting this information.

Variable NO in file MEGANv31.tibet27km.CB6.2022208.BDSNP.ncf you posted has NaN values, triggering the “floating invalid” error in line 1202 of desid_module.F

ncdump -v NO MEGANv31.tibet27km.CB6.2022208.BDSNP.ncf | more
netcdf MEGANv31.tibet27km.CB6.2022208.BDSNP {
dimensions:
TSTEP = UNLIMITED ; // (24 currently)
DATE-TIME = 2 ;
LAY = 1 ;
VAR = 34 ;
ROW = 115 ;
COL = 175 ;

…

0.04076951, 0.02598496, 0.03813488, 0.02312617, 0.02550854, 0.02628241,
0.02819956, 0.03518014, 0.03958071, 0.04633633, 0.06118023, 0.0765765,
0.0776834, 0.1098915, 0.08828563, 0.09810115, 0.07552952, 0.06449413,
0.03657012, 0.04044056, 0.03455531, 0.03459061, 0.03966175, 0.05362521,
0.04441707, 0.04557781, 0.05668181, 0.07518451, 0.04282502, 0.09871208,
0.1133665, 0.05309284, 0.09981976, 0.08575544, 0.1104998, 0.1180587,
0.09632298, 0.06107902, 0.07439312, 0.06171234, 0.04607532, 0.04027174,
0.07896861, 0.07552825, 0.07604636, 0.05142521, 0.1081867, 0.1213024,
0.09291191,
NaNf, NaNf, NaNf, 0, NaNf, 0, 0, 0.01823319, 0.09218207, 0.08048284,
0.07364602, 0.06272718, 0.03523219, 0.05210138, 0.03227433, 0.0144209,
0.01159746, 0.04796189, 0.09070752, 0.132624, 0.1437462, 0.1506041,
0.1539077, 0.1633602, 0.1727416, 0.1531, 0.157237, 0.1827559, 0.1820252,
0.1411281, 0.1227397, 0.1222927, 0.1240441, 0.1176117, 0.1220557,

The white pixels in this plot of variable NO from your file correspond to the NaN values:

image
image1258×496 75.8 KB

@willison.jeff had suggested to you in your previous thread to consider using the CMAQ MEGAN inline feature, rather than running MEGAN offline and providing that gridded emission file (MEGANv31.tibet27km.CB6.2022208.BDSNP.ncf) as input to CMAQ. In his post above, the comment about CMAQ checking for these NaN values and setting them to zero refers to running MEGAN inline in CMAQ, not running MEGAN offline.