according to your script, we can say that 'numRun'. as number of symbols
the problem is we run with a lot of symbol, and every symbol must choose the lowest papr, every symbol has their own phase rotation
The whole idea of SLM method is to generate a set of alternative data blocks and select the one with the lowest PAPR to transmit. Say, your original data has a PAPR of 12 dB and you multiply your original data with 4 phase sequences which yields 4 set of different data blocks. Let say one of the data blocks has a PAPR of 9 dB which is the minimum among 4 of them. So, the entire process reduce the PAPR from 12 dB to 9 dB.