A new computational method for quantitative determining the active component of Chinese medicine is proposed. Principle component analysis (PCA) was integrated with generalized rank annihilation factor analysis (GRAFA) to process HPLC/DAD data and the traditional IND function was revised. This new method can be used for computing the contents of available components in a complicated mixture. The method was applied to analyze the concentration of the component named notoginsenoside R_1 in a compound Chinese medicine, which was a mixture of Radix Salviae Miltiorrhizae and Radix Notoginseng. It was verified that the method was more accurate and reliable than CRAFA. Besides, the accuracy of computational analysis was substantially enhanced by modifying IND function.

Key words: COMPOUND PRESCRIPTIONS, PHARMACEUTICAL PREPARATION, ACTIVITY, COMPONENTS, PRINCIPAL COMPONENTS ANALYSIS, CHINESE DRUG, ANALYSIS, STOICHIOMETRY, HIGH-SPEED LIQUID CHROMATOGRAPHY, FACTOR ANALYSIS