Generate an isotope delta value object. See isotopia for general information on initializing
and converting isotope data objects. Delta values can be easily converted from values in one notation to values in
another notation by using `switch_notation`

.

delta(..., major = get_iso_opts("default_major"), compound = "",
ref = "", ref_ratio = numeric(),
notation = get_iso_opts("default_delta_notation"),
weight = numeric(), single_as_df = FALSE)

## Arguments

... |
- numeric vectors (can be named) to turn into delta values |

major |
- name of the major isotope in the isotope system [optional] |

compound |
- name of the compound the isotopic values belong to [optional] |

ref |
- name of the reference material |

ref_ratio |
- value of the reference material |

notation |
- which notation the value is in, `"permil"` (1000x multiplicaiton),
`"raw"` (raw value, i.e. no multiplication) and `"ppm"` (10^6 multiplicaiton)
are currently implemented for `delta` values. See `switch_notation` on
details how to convert between notations. |

weight |
- weight the isotope value (with a mass, concentration, etc.) for easy mass balance calculations.
The default value is 1, i.e. an unweighted isotope value.
If specified, `weight` must be a single value or a numeric vector of the same size as the data values.
The weight of an isotope value obejct can be retrieved and (re)set with the `weight` function. |

## Details

For mass balance calculations with delta values, simply add the appropriate weights (if different from
the default) and use `delta(...) + delta(...)`

.

## See also

## Examples

delta(50, notation = "permil") # enter as permil value

#> An isotope value object of type 'Delta value': d [permil]
#> [1] 50

delta(0.05, notation = "raw") # enter as non-permil value

#> An isotope value object of type 'Delta value': d
#> [1] 0.05