R: Get the location (model, matrix, row, column) and other info...

omxLocateParameters {OpenMx} | R Documentation

## Get the location (model, matrix, row, column) and other info for a parameter

### Description

Returns a data.frame summarizing the free parameters in a model, possibly filtered using ‘labels’.

For each located parameter, the label, model, matrix, row, col, value, and lbound & ubound are given as a row in the dataframe.

Duplicated labels return a row for each location in which they are found.

### Usage

    omxLocateParameters(model, labels = NULL, indep = FALSE, free = c(TRUE, FALSE, NA))

### Arguments

`model` | a MxModel object
`labels` | optionally specify which free parameters to retrieve.
`indep` | fetch parameters from independent submodels.
`free` | fetch either free parameters (TRUE), or fixed parameters or both types. Default value is TRUE.

### Details

Invoking the function with the default value for the ‘labels’ argument retrieves all the free parameters. The ‘labels’ argument can be used to select a subset of the free parameters. Note that ‘NA’ is a valid input to ‘labels’.

### See Also

`omxGetParameters`, `omxSetParameters`, `omxAssignFirstParameters`

### Examples

    A <- mxMatrix('Full', 2, 2, labels = c("A11", "A12", NA, "A11"), values= 1:4,
       free = TRUE, byrow = TRUE, name = 'A')

    model <- mxModel(A, name = 'model')

    # Request all free parameters in model
    omxLocateParameters(model)

    # Request free parameters "A11" and all NAs
    omxLocateParameters(model, c("A11", NA))

    # Works with submodel
    B = mxMatrix(name = 'B', 'Full', 1, 2, labels = c("B11", "notme"),
      free = c(TRUE, FALSE), values= pi)
    model <- mxModel(model, mxModel(B, name = 'subB'))

    # nb: only returns free parameters ('notme' not shown)
    omxLocateParameters(model)

[Package OpenMx version 2.20.6 Index]