is.valid.formula {RMassBank} | R Documentation

## Check validity of formula

### Description

Checks whether the formula is chemically valid, i.e. has no zero-count or negative-count elements.

### Usage

    is.valid.formula(formula)

### Arguments

`formula` | A molecular formula in string or list representation (`"C6H6"` or `list(C=6,H=6)`).

### Details

The check is only meant to identify formulas which have negative elements, which can arise from the subtraction of adducts. It is not a high-level formula "validity" check like e.g. the Rcdk function `isvalid.formula` which uses the nitrogen rule or a DBE rule.

### Author(s)

Michael Stravs

### See Also

`list.to.formula`, `add.formula`, `order.formula`

### Examples

    #
    is.valid.formula(list(C=0,H=1,Br=2))
    is.valid.formula("CH2Cl")
    is.valid.formula("C0H2")

[Package RMassBank version 3.2.0 Index]