calculate duration on a custom time stamp

[twilishyflutter]

my time stamps are in %H:%M format. one of which is a custom time stamp from my json file.
is there a way i can calculate the duration with this timestamp

[cmerriman]

try something like:

| eval newTime=strptime(timeStr, "%H:%M")

to convert the timestamps and then you should be able to use that in an eval to substract timestamps.