Cacher is the code snippet organizer for pro developers

# a quick look at a (pseudo) random section of this data
chla_mean[35:37, 245:247]

##           [,1]      [,2]      [,3]
## [1,] 0.1415056 0.1358830 0.1303250
## [2,] 0.1339336 0.1328560 0.1255906
## [3,] 0.1358152 0.1276533 0.1243571

# Change the dimension names of our matrix to "lon" and "lat", 
# and the row and column names to the latitude and longitude values.
dimnames(chla_mean) <- list(lon=nc_lon, lat=nc_lat)
chla_mean[35:37, 245:247]

##                   lat
## lon                -36.4791717529297 -36.5208358764648 -36.5625038146973
##   16.6458396911621         0.1415056         0.1358830         0.1303250
##   16.6875057220459         0.1339336         0.1328560         0.1255906
##   16.7291717529297         0.1358152         0.1276533         0.1243571

# lastly, you may want to transpose this matrix.
chla_mean <- t(chla_mean)
chla_mean[245:247, 35:37]

##                    lon
## lat                 16.6458396911621 16.6875057220459 16.7291717529297
##   -36.4791717529297        0.1415056        0.1339336        0.1358152
##   -36.5208358764648        0.1358830        0.1328560        0.1276533
##   -36.5625038146973        0.1303250        0.1255906        0.1243571