Hi I'm new here. For tinkering I run Processing 1.5.1 and Arduino 1.0. I'm trying to test some bunches of code but I think I do some very basics wrong...
For example: When I load GPS_MTK_test.pde which is

// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: t -*-
/*
Example of GPS MTK library.
Code by Jordi Munoz and Jose Julio. DIYDrones.com

Works with Ardupilot Mega Hardware (GPS on Serial Port1)
*/
#include
#include
#include

FastSerialPort0(Serial);
FastSerialPort1(Serial1);

AP_GPS_MTK gps(&Serial1);
#define T6 1000000
#define T7 10000000

void setup()
{
Serial.begin(38400);
Serial1.begin(38400);
stderr = stdout;
gps.print_errors = true;

Serial.println("GPS MTK library test");
gps.init(); // GPS Initialization
delay(1000);
}
void loop()
{
delay(20);
gps.update();
if (gps.new_data) {
Serial.print("gps:");
Serial.print(" Lat:");
Serial.print((float)gps.latitude / T7, DEC);
Serial.print(" Lon:");
Serial.print((float)gps.longitude / T7, DEC);
Serial.print(" Alt:");
Serial.print((float)gps.altitude / 100.0, DEC);
Serial.print(" GSP:");
Serial.print(gps.ground_speed / 100.0);
Serial.print(" COG:");
Serial.print(gps.ground_course / 100.0, DEC);
Serial.print(" SAT:");
Serial.print(gps.num_sats, DEC);
Serial.print(" FIX:");
Serial.print(gps.fix, DEC);
Serial.print(" TIM:");
Serial.print(gps.time, DEC);
Serial.println();
gps.new_data = 0; // We have readed the data
}
}

I get some errors:
processing.app.SketchException: unexpected char 'i'
at processing.mode.java.JavaBuild.preprocess(JavaBuild.java:353)
at processing.mode.java.JavaBuild.preprocess(JavaBuild.java:197)
and many more

I asked google but haven't found an satisfieing answer to the prob. Does this unexpected char 'i' error thing come from outside of the code or something?

After that I loaded the same file GPS_MTK_test.pde to the Arduino IDE. Do I have to worry about the .pde extension here? Anyway, I get:
AP_Math.h: No such file or directory

Hmm. But this very AP_Math.h is in
C:\AVR\Arduino_stuff\arduino-1.0-windows\arduino-1.0\libraries\AP_Math
So I think the location is right.

What's going on here?