CorMID (version 0.3.1)

CountChemicalElements: CountChemicalElements.

Description

CountChemicalElements will split a character (chemical formula) into its elements and count their occurrence.

Usage

CountChemicalElements(x = NULL, ele = NULL)

Value

A named numeric with counts for all contained or specified elements.

Arguments

x

Chemical formula.

ele

Character vector of elements to count particularly or counting all contained in string if NULL.

Details

No testing for any chemical alphabet is performed. Elements may occur several times and will be summed up in this case without a warning. Information within brackets, i.e. [13]C will be removed prior to counting together with other symbols not contained in the R set 'alnum'. The result is filtered and ordered according to parameter 'ele' if provided.

Examples

# count every element
CountChemicalElements("C3H7Cl")

# remove additional symbols and sum up redundant elements (here 'C')
CountChemicalElements("[13]CC2H8Cl+")

# count specific elements and return in specified order
CountChemicalElements("[13]CC2H8Cl+", ele=c("Cl","O","H"))

# apply on a vector of formulas using sapply
sapply(c("C3H7Cl", "[13]CC2H8Cl+"), CountChemicalElements, ele=c("Cl","O","H"))