This will work absolutely fine for Numbers; whereas PurgeChar function will not work when there will be zero's in between of given field value. BTW, I am working on to get the 100% correct solution. Soon I will update you on this.
Num() will strip the leading zeroes from the numreric values.
For the alpha values, replace the 0's with spaces, add a 'fence' to prevent removing trailing zeroes, trim, replace the spaces with zeroes again. This assumes that there are no spaces inthe source field.
Logic will get you from a to b. Imagination will take you everywhere. - A Einstein