Get reaction chain for specific mass to charge ratio

```
getchain(
list,
diff,
mass,
digits = 2,
accuracy = 4,
rtcutoff = 10,
corcutoff = 0.6,
ppm = 25
)
```

## Arguments

- list
a list with mzrt profile

- diff
paired mass distance(s) of interests

- mass
a specific mass for known compound or a vector of masses. You could also input formula for certain compounds

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

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

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

- corcutoff
cutoff of the correlation coefficient, default 0.6

- ppm
all the peaks within this mass accuracy as seed mass or formula

## Value

a list with mzrt profile and reaction chain dataframe

## Examples

```
data(spmeinvivo)
# check metabolites of C18H39NO
pmd <- getchain(spmeinvivo,diff = c(2.02,14.02,15.99),mass = 286.3101)
```