Removing the period is easy replace({somefield},".","").  Can't think of an easy way to get rid of the numbers.  A for loop to look at each character and see if it is numeric, if so.  Remove the number out of the string.

There are two solutions. I am not sure what the results will be in memoryusage / performance.

1. A nested replace

replace(replace(replace(replace(replace(replace(replace(replace(replace(replace(replace({somefield},".",""),"0",""),"1",""),"2",""),"3",""),"4",""),"5",""),"6",""),"7",""),"8",""),"9","")

2. use a function:

Function (stringvar inString)

(

    Local Stringvar outString := "";

    Local Numbervar i;

    For i :=1 To Length(inString) Do

    (

        If inStr("0123456789.", inString) =0 Then

        (

            outString := outString + inString;

        )

    );

outString

)