How are they downloaded?
What something do they do?
Perhaps stepping back a bit and considering the rest of the program in terms of this might help:
Since the details of the reading and the using aren't presented in the thread, this assumes that you already have those handled adequately, and you are focused on how to do the looping. loop() will handle that:
int x,y;
void setup(){
}
void loop() {
readXnY();
useXnY();
}
void readXnY(){
//
}
void useXnY(){
y;
x;
}
where useXnY(){...} holds what you've shown in the for loop.
That untested snippet should does run.