processingでjavaScriptのeval関数を使う

import javax.script.*;

import java.util.*;

void setup(){

initialize();

calc("cos(radians(90))");

}

ScriptEngineManager factory = new ScriptEngineManager();

ScriptEngine engine = factory.getEngineByName("JavaScript");

String simu(String eval) {

try {

return( engine.eval("with(Math){"+eval+"}").toString() );

}

catch(Exception e) {

return(null);

}

}

String calc(String str) {

String ans=simu(str);

if(ans==null)return "その式ちょっとわからない…";

return str+"の式の答えは"+ans+"だよ！！";

}

void initialize()() {

simu("function radians(x){return(x/180*PI);}");

simu("function degrees(x){return(x/PI*180);}");

simu("function sinDeg(x) {return(sin(radians(x)));}");

simu("function cosDeg(x) {return(cos(radians(x)));}");

simu("function tanDeg(x) {return(tan(radians(x)));}");

String test = "function sum(a)"

+ "{var s=0;"

+ "for(var i=0; i< a.length; i++) s+=a[i];"

+ "return(s);}";

simu(test);

}