Re: Calculating/Averaging over a struct value

[Timon Gehr]

#! /usr/bin/rdmd

import std.array;
import std.csv;
import std.stdio;
import std.string;
struct Data{
    string Date;
    double d1;
    double d2;
    int i4;
}

double average(Data[] x, string para){
    double result = 0.0;
    theswitch:switch(strip(para)){
            foreach(member;__traits(allMembers, Data)){
                case member:
                    static if(__traits(compiles, 
{result+=mixin(`x[0].`~member);})){
                        foreach(d; x){
                            result+=mixin(`d.`~member);
                        }
                    }else{
                        throw new Exception("don't know how to average 
over "~para);
                    }
                    break theswitch;
        }
        default: throw new Exception("no member named "~para);
    }

    return result/x.length;
}

void main(){
    Data[] allData;
    string text= "2011-11-30,2.25,3.00,100\n2011-11-29,2.24,2.75,1000\r\n";

    foreach(ob;csvReader!Data(text)){
            allData ~= ob;
    }

    writeln(allData);

    string input;
    writeln("Enter the variable you would like to average over: ");
    stdin.readln(input);
    try writeln(average(allData,input));
    catch(Exception e){writeln(e.msg);}
}