extractMoreauBroto fails when the sequence is shorter than the lag

[koefoed]

extractMoreauBroto fails when nchar(x) <= nlag without a propper error message:

> packageVersion('protr')
[1] ‘0.5.1’
> extractMoreauBroto("STHIYTKE")
Error in P[[i]][1:(N - j)] : 
  only 0's may be mixed with negative subscripts

[VeenaPulicharla]

Hi, I don't belong to Bioinformatics background, I am trying this package for some project, I have peptide sequences, I would like to derive some features from it to use as input to machine learning model. Could someone explain the reason for this error, "extractMoreauBroto: length of the sequence is <= nlag; NAs will be generated",

• why it doesn't accept sequences with shorter length ?

• what are the min and max limits for sequence length limits?

• I have many sequences with length in range of 5 to 25, how to extract features from these sequences, any suggestions?