How to declare all the variables in Setup() for my program.

Projects Programming
1

Hello, I'm trying to solve the following question i.e in the below picture given for my homework.

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I came up with the following code until now, however it does not fully meet the requirements

double n                  = 0;
double MMAn_1             = 0;
double MMAn               = 0;
double SIG2n_1            = 0;
double SIG2n              = 0;
double sum                = 0;
double sum_of_sqr         = 0;
double random_number      = 0;
double Xn                 = 0;
double standard_deviation = 0;
void setup() {
  // put your setup code here, to run once:
Serial.begin(9600);
Serial.println("Enter Window Size");
while(Serial.available()==0);
n = Serial.parseInt();
Serial.print  ("Window size is "); 
Serial.println(n);
Serial.println("Generating Random Numbers . . . ");
delay(1000);
for(int i = 0 ; i<n ; i++){
random_number = random(101);
Serial.println(random_number);
delay(300); 
sum = sum + random_number;
sum_of_sqr = sum_of_sqr + random_number*random_number;
}
MMAn_1  = sum/n;
SIG2n_1 = (sum_of_sqr - (sum*sum)/n)/n ;
}

void loop() {
  // put your main code here, to run repeatedly:
MMAn  = ((n-1)*MMAn_1 + Xn)/n;
SIG2n = ((Xn - MMAn_1)*(Xn - MMAn) + (n-1)*SIG2n_1)/n;
standard_deviation = sqrt(SIG2n);
Serial.print  ("Moving Average     = "); 
Serial.println(MMAn);
Serial.print  ("Standard Deviation = ");
Serial.println(standard_deviation);
 MMAn_1 = MMAn;
 SIG2n_1 = SIG2n;
Serial.println("Generating New Random Number . . . ");
delay(2000);
Xn = random(101);
Serial.println(Xn);
n = n+1;
}

How do you think I can
1.declare all variables inside the setup.
2. seed using input from unused pin A0.

3

as for question 2.
randomSeed(analogRead(A0)); will do the trick
as for question 1, well.. you have declared them all before setup(), which is correct, since if you would declare them inside setup() they would be local to the function and not usable outside of it. I am puzzled by that one..

4

Deva_Rishi:
as for question 2.
randomSeed(analogRead(A0)); will do the trick
as for question 1, well.. you have declared them all before setup(), which is correct, since if you would declare them inside setup() they would be local to the function and not usable outside of it. I am puzzled by that one..

It worked! Thank You.

Do you think my rest of the program leaving the variable declaration is correct?

6

As I understand it, it doesn't say to declare all variables in setup()...

(a) Declare all necessary variables.

Then in setup() do:
(b)
(c)
(d)

Then in loop(), do :
(e)
(f)
etc ...

7

Yeah makes sense. I kinda over thought the question.
Thanks a ton!