Making a dataframe from multiple (say 50) lists with differing lengths using for loop

[technocrat]

@apustat

x= matrix(rnorm(np1), nrow = n, ncol = p1) #without intercept

np1 is missing. To avoid problems like this, use a reprex. See the FAQ: How to do a minimal reproducible example reprex for beginners.

Generating a reprex uses a fresh session to assure that everything referenced in the code is there.