You almost got it

model sample1

  parameter Real x[5] = 1:5; //So this line should create a file column 1 row array. from 1,2,3,4,5

  parameter Real p=5;

  Real y[5]; // here i am telling OpenModelica that this y-array is also 5 columns wide

  Real z;

equation

  y = p * x; // here i should multiply the array by the the real value, unfortunatelly this is not happening, in fact the code is not working it all.

  z = sum(y); //here i should be able to add the all of the columns of y-array to get my sum.

end sample1;

Adrpo,

Thank you so much, that worked!! 

Thank you again for your feedback. I have another question. I updated the code to try to get the following to work. However, i keep getting an error in variable "u". Open Modelica tells me that this cannot be solved bcause the operation is of integer type. Any help will be appreciated thank you.

model sample1
parameter Real x[5] = 1:5;
extends Modelica.Constants;
Modelica.SIunits.Length L = 2;
Real y[5];
Real p[5];
Real u[5];
Real z;
equation
u = x*pi/L;
p = ((e^(-1*((u)^2)*t)-1)/x^3); /*/here i have a problem where u cannot be solved because it is of type integer? But i am not sure what it should be then /*/ 
u =x*pi/L;
y = L * pi * x;
z = sum(y);
end sample1;

You need to use the element-wise operators .^ .- and ./ instead of ^ - and /.

Just an update, thanks sjoelund.se, the advice helped. The code runs just fine now. I am placing the updated code here so it may help others who have the same question.

model sample1
parameter Real x[5] = 1:5;
extends Modelica.Constants;
Modelica.SIunits.Length L = 2;
Real y[5];
Real p[5];
Real u[5];
Real z;
Real t = time;
equation
u = (x.*pi)./L;
p = ((e.^(-1.*((u).^2).*t).-1)./x.^3);
y = L * pi * x;
z = sum(y);
end sample1;