Predicting Khums in the Iranian Economy for Establishing Islamic Treasury by designing the Fourier series equation

Khums in Islam, especially among Shiite communities, is one of the most important religious aspects for the establishment of the Islamic economy. Islamic economics is very important for creating an Islamic treasury. The purpose of this good descriptive-exploratory research is to fit the calculations made of the country's potential Khums during the years 1380 to 1393 and design a mathematical equation to predict the amount of potential Khums in the Islamic economy of Iran using the quadratic equation of the Fourier series in Matlab software. While calculating the types of Khums, the results of the research have a coefficient of determination R2 equals to 0.9521 for total Khums, 0.9027 for revenue Khums and 0.9561 for mining Khums and a modified coefficient of determination R2 Adjustment are 0.8443, 0.7892 and 0.9048, respectively, with a coefficient of correlation 95% was obtained, which indicates the goodness of accurate fit of the calculations. In this article, for each of the two Khums, the calculation formula with the output of specific coefficients recorded by MATLAB software is presented, which is an efficient method in predicting results in other sciences; which is able to accurately predict the types of Khums in the treasury of the Islamic economy of Iran.