[R] Removing points

I have a some data, and imagine a column of how many parasitic eggs found in the stool of some children some of the children we do not have this data so we put -1 in stead. How can you remove the people with -1, to calculate means and do box plots. Thank you! -- View this message in context: htt

[R] More complex historgram

CID DISTRICTSCHOOL YRofSTUDY DATE.ENTRY SEX AGE EGGS.M EGGS.MIIEGGS.H POBADN0130 PO Badongo 0 18.1.08 2 11 0 -1 73 POBADN0117 PO Badongo 0 18.1.08 1 10 0 -1 59 POBADN0160 PO