data() {
# target, feature, weight, filter
	cat<<EOF
     co,      AS,   0.35,      1
     co,      PF,   0.65,      1
     ep,      CX,  0.547,  0.172
     ep,      DI,  0.351,  0.172
     ep,      SS,  0.102,  0.172
     ep,      EX,  0.828,  0.579
     ep,      DO,  0.172,  0.579
     ep,      RA,  0.226,  0.249
     ep,      AM,  0.242,  0.249
     ep,      US, 0.0955,  0.249
     ep,      UC, 0.0962,  0.249
     ep,      CL, 0.0764,  0.249
     ep,      FR,  0.119,  0.249
     ep,      DT, 0.0873,  0.249
     ep,      RM, 0.0647,  0.249
EOF
}

data > /tmp/w

gawk -F, 'Pass==1 {sum[$1] +=  $3*$4} 
		  Pass==2 { printf("%s,%5.3F,%5.1f\n", $0,$3*$4,int(100*$3*$4)/sum[$1])}' \
		Pass=1 /tmp/w Pass=2 /tmp/w