SOM Toolbox | Online documentation | http://www.cis.hut.fi/projects/somtoolbox/ |

Undo normalizations of data structs/sets.

sS = som_denormalize(sS) sS = som_denormalize(...,'argID',value,...); sS = som_denormalize(...,value,...); D = som_denormalize(D,sNorm)

This function is used to undo normalizations of data structs/sets. If a data/map struct is given, all normalizations in the '.comp_norm' field are undone and, thus, the values in the original data context are returned. If a matrix is given, the normalizations to undo must be given as the second argument. SOM_DENORMALIZE actually uses function SOM_NORM_VARIABLE to handle the normalization operations, and only handles the data struct/set specific stuff itself. Normalizations are always one-variable operations. In the data and map structs the normalization information for each component is saved in the '.comp_norm' field, which is a cell array of length dim. Each cell contains normalizations for one vector component in a struct array of normalization structs. Each component may have different amounts of different kinds of normalizations. Typically, all normalizations are either 'undone' or 'done', but in special situations this may not be the case. The easiest way to check out the status of the normalizations is to use function SOM_INFO, e.g. som_info(sS,3)

sS The data to which the denormalization is applied. (struct) Data or map struct. The normalizations in the '.comp_norm' field are undone for the specified components. (matrix) Data matrix. The normalization to undo must be given in the second argument.

argID (string) Argument identifier string (see below). value (varies) Value for the argument (see below). The optional arguments can be given as 'argID',value -pairs. If an argument is given value multiple times, the last one is used. The valid IDs and corresponding values are listed below. The values which are unambiguous (marked with '*') can be given without the preceeding argID. sNorm *(struct) Normalization struct, or an array of structs, which is undone for all specified components. If the '.status' field of the struct(s) is 'uninit', the undoing operation is interrupted - it cannot be done. Alternatively, the struct may be map or data struct in which case its '.comp_norm' field is used (see the cell array option below). *(cell array) In practice, the '.comp_norm' field of a data/map struct. The length of the array must be equal to the dimension of the given data set (sS). Each cell contains the normalization(s) for one component. Only the normalizations listed in comps argument are undone though. 'remove' *(string) If 'remove' tag is specified, the normalization operations are not only undone, they are also removed from the struct. 'comps' *(vector) The components which are denormalized. Default is to undo all components. *(string) 'all'

sS Modified and/or updated data. (struct) If a struct was given as input argument, the same struct is returned with denormalized data and updated '.comp_norm' fields. (matrix) If a matrix was given as input argument, the denormalized data matrix is returned.

To undo normalization of a data/map struct: sD = som_denormalize(sD); sM = som_denormalize(sM); To completely remove the normalizations, use the 'remove' tag: sD = som_denormalize(sD,'remove'); To undo only a few selected components, use the comps argument: sD = som_denormalize(sD,[1 3:5]); To denormalize a set of values from a data set D (which must be of equal dimension as the data in sD): D = som_denormalize(D,sD); or D = som_denormalize(D,sD.comp_norm); only denormalize a few components D = som_denormalize(D,sD,[1 3:5]); Assuming you have a few values of a certain vector component (i) in a vector (x) which you want to denormalize: xorig = som_denormalize(x,sD.comp_norm{i}); or using SOM_NORM_VARIABLE xorig = som_norm_variable(x,sD.comp_norm{i},'undo'); To check out the status of normalization in a struct use SOM_INFO: som_info(sM,3) som_info(sD,3)

som_normalize
| Add/apply/redo normalizations of a data struct/set. |

som_norm_variable
| Normalization operations for a set of scalar values. |

som_info
| User-friendly information of SOM Toolbox structs. |