1970113.00000 3460.00000 1.09516 
1970116.00000 3791.00000 1.06350 
1970120.00000 4120.00000 1.07588 
1970115.00000 4450.00000 1.09591 
1970116.00000 4780.00000 1.09965 
1970120.00000 5109.00000 1.06733 
1970122.00000 5440.00000 1.03760 
1970124.00000 5770.00000 1.02025 
1970123.00000 6100.00000 1.00998 
1970120.00000 6430.00000 0.96426

For each line (#NR= 1 to 10) I would like to search X($1),Y($2) within the I/P file  which lies within a radius of 50 and then average out all the $3 within that circle of radius 50.

 
set first = 1    # NR=1 ; first line fo the input file
set last = 10   # NR = 10; Last line of the input file
 
set num = ${first}
while (${num} <= ${last})
 
set X0 = `cat S2 | awk -v line=${num} 'NR==line' | awk '{print $1}'` # $1,X, for each Record
set Y0 = `cat S2 | awk -v line=${num} 'NR==line' | awk '{print $2}'` # $2,Y, for each Record
set XS = `cat S2 | awk -v line=${num} 'NR==line' | awk '{print $3}'` # $3,Value that will be averaged out, for each Record
set R0 = `echo "50"` # Search radius
 
set AVG = `cat S2 | awk -v X=${X0} -v Y=${Y0} -v R=${R0} '{print $1,$2,$3,sqrt(($1-X)*($1-X) + ($2-Y)*($2-Y)) <=R}'  | awk '{if($4==1){print $0}}' | awk '{ sum+=$3} END {print sum/NR}'`# Search all the points within the input file which lies within R #Average all the $3,values#
 
echo "${X0} ${Y0} ${XS} ${AVG}" >> TMP #For each record print a new line with existing $1,$2,$3 and $AVG
 
@ num++ # end of loop and it goes to next NR
end