named list with results from all three methods
all_ptr dataframe with the estimated PTRs on success, null otherwise
est_ptr: estimated PTR values
coefficient: coefficient of linear regression
pValue: p-value of linear regression
cor: correlation coefficient
correctY: corrected coverage
contigs_ptr dataframe with the estimated PTRs on success, null otherwise
est_ptr: estimated PTR values
coefficient: coefficient of linear regression
pValue: p-value of linear regression
cor: correlation coefficient
correctY: corrected coverage
samples_ptr dataframe with the estimated PTRs on success, null otherwise
est_ptr: estimated PTR values
coefficient: coefficient of linear regression
pValue: p-value of linear regression
cor: correlation coefficient
correctY: corrected coverage