Table 1.

Effective wavenumbers selected by PCA loadings.

Methods	No.	Effective Wavelengths (nm)
PCA loadings	43	1009, 1025, 1032, 1052, 1069, 1082, 1096, 1116, 1119, 1123, 1126, 1130, 1200, 1204, 1224, 1227, 1230, 1241, 1264, 1268, 1308, 1315, 1318, 1321, 1342, 1345, 1362, 1386, 1396, 1399, 1402, 1409, 1426, 1443, 1450, 1453, 1456, 1470, 1548, 1554, 1588, 1598, 1602