libTF

Library "libTF"
libTF: Find higher/lower TF automatically
This library to find higher/lower TF from current timeframe(timeframe.period) for Pine Script version6(or higher).

Basic Algorithm
Using a timeframe scale Array and timeframe.in_seconds() function to find higher/lower timeframe.
Return value is na if could not find TF in the timeframe scale.
The timeframe scale could be changed by the parameter 'scale'(CSV).

How to use
1. Set higher/lower TF
higher()/lower() function returns higher/lower TF.
Default timeframe scale is "1, 5, 15, 60, 240, 1D, 1M, 3M, 12M".
example:

htf1 = higher()
htf2 = higher(htf1)
ltf1 = lower()
ltf2 = lower(ltf1)

2. Set higher/lower TF using your timeframe scale
The timeframe scale could be changed by the parameter.
example:

myscale="1,60,1D,1M,12M"
htf1 = higher(timeframe.period,myscale)
htf2 = higher(htf1,myscale)
ltf1 = lower(timeframe.period,myscale)
ltf2 = lower(ltf1,myscale)

3. How to use with request.*() function
na value is set if no higher/lower TF in timeframe scale.
It returns current timeframe's value, when na value as timeframe parameter in request.*().
As bellow, if it should be na when timeframe is na.
example:

return_value_request_htf1 = na(htf1)?na:request.security(syminfo.tickerid,htf1,timeframe.period)
return_value_request_ltf1 = na(ltf1)?na:request.security(syminfo.tickerid,ltf1,timeframe.period)

higher(tf, scale)
  higher: find higher TF from TF string.
  Parameters:
    tf (string): default value is timeframe.period.
    scale (string): TF scale in CSV. default is "1,5,15,60,240,1D,1W,1M,3M,12M".
  Returns: higher TF string.

lower(tf, scale)
  lower: find lower TF from TF string.
  Parameters:
    tf (string): default value is timeframe.period.
    scale (string): TF scale in CSV. defalut is "1,5,15,60,240,1D,1W,1M,3M,12M".
  Returns: lower TF string.