calcuations in adobelivecycle

Hello

i have made a form using adobe livecycle designer and i need to make calculations in the form.

this calcuation include:

1- i want to get average of 4 numeric values and put the average in another field> example; i have Cell A,B,C,D which are numeric, i want to obtain the average of the 4 values and put it in cell2

2- i want to obtain the standard deviation for about 4 cells which are numeric

( in adobe acrobat pro i was using this code:

var MyValues = new Array();

var MyFields = new Array("F0VerHR", "F1VerHR", "F1secondVerHR", "F2VerHR", "F3VerHR");

var oField;

var nField;

for(var i = 0; i < MyFields.length; i++)

{

  nField = '';

  nField = GetField(this, MyFields[i]).valueAsString;

  if(nField != "") MyValues.push(Number(nField));

}

event.value = standardDeviation(MyValues);

i hope some one help me in that ane if any one have any pdf explain all calcultions that can be performed and codes.

thanks