findMzGroup,proFIAset-method {proFIA} | R Documentation

## find a group in a FIA experiment.

### Description

Find a group corresponding to the given mass in a proFIAset object, given a tolerance in ppm.The mz considered for a group is the median fo the grouped signals between the various acquisition.

### Usage

    ## S4 method for signature 'proFIAset'
    findMzGroup(object, mz, tol, dmz = 0.005, closest = TRUE)

### Arguments

`object` | A proFIAset object.
`mz` | A numeric vector of masses to be looked for.
`tol` | The tolerance in ppm.
`dmz` | The minimum tolerance in absolute mz compared to the tolerance in ppm.
`closest` | Shall only the closest group be returned.

### Value

A vector of integer of the same length than mz giving the row of the found group in the object group slot, or NA if the group is not found.

If closest is FALSE a list giving the index of the found group, if closest is TRUE a vector giving the position. NA indicates that the mass signal have not bene found.

### See Also

You can visualize the group using `plotFlowgrams` function.

### Examples

    if(require("plasFIA")){
    #proFIAset object is loaded
    data(plasSet)

    #The table of spiked molecule is loaded
    data(plasMols)

    #Mass to search and toolerance are defined
    mass<-plasMols[22,"mass_M+H"]
    tolppm <- 1

    plasSet<- makeDataMatrix(plasSet)

    index <- findMzGroup(plasSet,mass,tol=tolppm)

    plasMols[22,]
    #We extract the corresponding group.
    groupMatrix(plasSet)[index,]
    }

[Package proFIA version 1.18.0 Index]