proc format_usd {num {sep ,}} {
# Find the whole number and decimal (if any)
set whole [expr int($num)]
set decimal [expr $num - int($num)]
#Basically convert decimal to a string
set decimal [format %0.2f $decimal]
# If number happens to be a negative, shift over the range positions
# when we pick up the decimal string part we want to keep
if { $decimal <=0 } {
set decimal [string range $decimal 2 4]
} else {
set decimal [string range $decimal 1 3]
}
# If $decimal is zero, then assign the default value of .00
# and glue the formatted $decimal to the whole number ($whole)
if { $decimal == 0} {
set num $whole.00
} else {
set num $whole$decimal
}
# Take given number and insert commas every 3 positions
while {[regsub {^([-+]?\d+)(\d\d\d)} $num "\\1$sep\\2" num]} {}
# Were done; give the result back
return $num
}
