Adding Scientific Functions to a Web Page Calculator
In this last part of our six-part series, we shall talk about adding scientific functions to our web page calculator, and then conclude. Scientific functions refer to functions like sin(?), cos(?), tan(?), and log(x). The process is not as difficult as you think. The JavaScript interpreter incorporated into many browsers has some built-in scientific functions. It has most of the functions we shall use. However, it does not have some of the functions we shall use. We shall have to code the pair of functions that JavaScript does not have.
Adding Scientific Functions to a Web Page Calculator - The Global Variables (Page 4 of 4 )
var showNumCalledOnce = false;
This variable is used by the showNum(ID) and operator(ID) function..
var evalString = "";
This variable is used by the removeCalc() and operator(ID) functions.
var memVar = "";
This variable is used by the removeCalc(), showNum(ID) and operator(ID) functions.
var toClearDisplay = false;
This variable is used by the showNum(ID), operator(ID and scienceFn(ID) functions.
var baseExp = false;
This variable is used only by the operator(ID) function.
Your Commercial Project
There are a few things I have not taken into consideration. For example, the number of decimal places for some results may be too long. You have to take this and a few other things into consideration, for you commercial project.
Well, this is the end of the series. I hope you appreciated it. I thank you for reading the series.
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Using the Keyboard with a Web Page Calculator
