Fig. 2.

The Fisher’s linear discriminant analysis results presented as accuracy with different times. a When taking 60 data samples as training samples and 8 data as test samples, the average accuracy rate was 92.64%. b When taking 50 data samples as training samples and 18 data as test samples, the average accuracy rate was 90.05%. c When taking 40 data samples as training samples and 28 data as test samples, the average accuracy rate was 88.57%