<< Click to Display Table of Contents >> Navigation:  Wadiso 6 User Guide > Optimization > Wadiso Optimization Data definition  > Cost Functions

Cost functions for pipe, pump and tank cost calculations are required for optimization data. The user may enter cost data in the cost data input portion of the program or use default cost data stored in the program. The data includes costs for each size for one or several cost functions. The user also indicates which pipe link belongs to which cost function. Costs are represented by a discrete function. The program does not need to interpolate points between sizes. Therefore no continuous price function needs to be fitted through the points. The price function does not need to meet any particular mathematical requirements (e.g. concave, linear, etc.). The user can build up to 8 cost functions. The default data for pipe cost is stored as price function 1 while default data for cleaning and re-lining of existing pipes is stored as price function 2. These default prices can be overwritten by the user by entering new data or retrieving previously stored data. When there are pumps in the system, the user specifies a unit cost for energy per kWh, and an interest rate and the number of years of operation, so that the program can calculate the present worth of pumping cost.