The Design And Implementation Of Scientific Calculator Support General Data Object

In the face of a large number of complex data, people need to find a more efficient computing solution, which needs help from a scientific calculator. Now the prices of scientific calculators are relatively low, but with the following disadvantages:the first one is that their functions are relatively simple and can only be applied in some specific computing areas, they support only simple, single step four arithmetic operations; the second one is that they only allows a user to input a long formula step by step, and causes low efficiency; the third one is that they does not support expressions containing logic computations, making the processes of some calculations very difficult, sometimes even making it unable to accurately calculate the data or even making it unable to allow users to input arithmetic expressions. Based on the above reasons, it is necessary to develop a scientific calculator which supports general data objects.After analysing the functions of mainstream scientific calculators and the actual needs in our work, we have designed and implemented a new scientific calculator supporting generic data. The system is developed based on Qt. It supports not only functions doing calculations through pre-defined formulas, and also functions allowing a user to manually input an arithmetic expression. It is able to recognize the input expression and do calculations over it. It can effectively reduce a large number of complex calculation errors and help users do data operations faster and more efficiently. It is very important to implement a calculator like this both from an application perspective and from an economic perspective.Based on an in-depth study on recursive step-by-step operations and the gradually-simplified method of parsing arithmetic expressions, we have mainly solved two problems. One is dealing with how to parse a user-input expression, converting a user-given, un-formal expression string to an arithmetic expression easy to process by the calculator; the other is data object abstraction, making the calculator support calculations composed of different data objects seamlessly and with the minimum cost.The calculator developed in this work is better than commonly-used scientific calculators in that it supports expressions containing logic values, it has solved two problems:one is how to parse a user-input expression, the other is data object abstraction. The solvation of these two problems making us able to accomplish our original intentions. This is the biggest feature of this project and is also what makes our calculator distinguished from other calculators.There are some deficiencies in the scientific calculator designed in this paper. The first one is that, in order to support versatility, flexibility and stability, some of the operational efficiency is sacrificed. The second one is that no optimization has been done over the calculation process. The third one involves some limitations over the calculation method itself, namely, neither adjacent sample points nor the concept "time window" have been introduced in the calculation process, causing operations like integrals which is often used in engineering mathematics can not be done by this calculator.We have considered when designing the calculator to add some special keywords to express complex integral operator, but because they often need precise control over subscripted variables (such as the summation operator), putting forward new problems involving cyclic operations of array data, which affects the whole control flow of the parsing process. Considering these negative effects on parsing complexity and stability, complex operators have not been implemented in this project, and we leave them to subsequent studies.