BiCalc: An Ethnomathematics-Based Calculator with Biak Language (Wos Byak) Number Translation on the Android Platform

Abstract

BiCalc is an Android calculator that shows every number and every calculation result at the same time as digits and as words in the Biak language (Wos Byak), so that everyday arithmetic becomes a way to learn Biak numerals. This study aims to design and implement the calculator with an ethnomathematics approach, that is, by treating the local number system as part of the software rather than as additional learning material. The method used is Research and Development (R&D), through the stages of requirements analysis, design, implementation, and testing. The application is built with Java in Android Studio, calculations use the BigDecimal class, and the conversion of numbers into Biak words is performed by a rule-based algorithm with the additive connector seser and the multiplicative connector ri. The conversion range is 0 to 999,999,999,999,999 and covers negative numbers and decimals. Functional testing shows that the application output conforms to the Biak number rules in the reference document: 1,043 of 1,044 reference rows match exactly. The application also provides Operation Tables for 1 to 10, three colour themes, two interface languages, and an adaptive layout for phones and tablets. BiCalc shows that a calculator can serve as a medium for preserving a regional language and, at the same time, as a tool for culture-based mathematics learning.