Linear Input Method of Mathematical Formula

Mathematical formula with two-dimensional structure has rich meanings. However, when input mathematical formula on the computer, we can only use finite characters on the keyboard to input string of one-dimensional characters. So the size and the position of a lot of signs and symbols can´t be input directly using the keyboard. In order to achieve fine input and display of mathematical formula, according to the study of existing six mathematical formula infix formats, and according to the characteristics of the education teaching rule, input habit of elementary mathematics teachers and students, from digital, Greek letters, operators, commonly used function four aspects developed a mathematical formula linear syntax format for Chinese users -- a mathematical expand infix language (MEIL). The experimental results show that, MEIL required least number of characters to input a mathematical formula, in line with the user habits and able to efficiently input, more convenient and flexible use by students.