How to interpret predicted data from a keras model
you have 99 leaf species and 594 test records. Also the output is (594,). Here each value represents corresponding leaf species columns index.
 check the species data you would have received after One-HotEncoder/get_dummies. 
each value of "computed_predictions" corresponds to their respective column number. 
you can export species column_name to a list(of 99 labels) and get the labels using list index(i.e. computed_predictions respective value)