Filter ions/peaks based on retention time hierarchical clustering, paired mass distances(PMD) and PMD frequency analysis.

Filter ions/peaks based on retention time hierarchical clustering, paired mass distances(PMD) and PMD frequency analysis.

getpaired(
  list,
  rtcutoff = 10,
  ng = NULL,
  digits = 2,
  accuracy = 4,
  mdrange = NULL
)

Arguments

list

a list with mzrt profile

rtcutoff

cutoff of the distances in retention time hierarchical clustering analysis, default 10

ng

cutoff of global PMD's retention time group numbers, If ng = NULL, 20 percent of RT cluster will be used as ng, default NULL.

digits

mass or mass to charge ratio accuracy for pmd, default 2

accuracy

measured mass or mass to charge ratio in digits, default 4

mdrange

mass defect range to ignore. Default NULL and c(0.25,0.9) to retain the possible reaction related paired mass

Value

list with tentative isotope, multi-chargers, adducts, and neutral loss peaks' index, retention time clusters.

See also

getstd,getsda,plotpaired

Examples

data(spmeinvivo)
pmd <- getpaired(spmeinvivo)
#> 75 retention time cluster found.
#> 369 paired masses found 
#> 5 unique within RT clusters high frequency PMD(s) used for further investigation.
#> The unique within RT clusters high frequency PMD(s) is(are)  28.03 21.98 44.03 17.03 18.01.
#> 719 isotopologue(s) related paired mass found.
#> 492 multi-charger(s) related paired mass found.