`omxSelectRowsAndCols`

### Description

The function `omxSelectRowsAndCols`

filters rows and columns from an mxMatrix using a single row or column R matrix as a selector. The function `omxSelectRows`

can be used to only filter rows and the function `omxSelectCols`

can be used to only filter columns.

### Usage

`omxSelectRowsAndCols(mxMatrixToBeFiltered, selectorMatrix)`

`omxSelectRows(mxMatrixToBeFiltered, selectorMatrix)`

`omxSelectCols(mxMatrixToBeFiltered, selectorMatrix)`

### Arguments

`mxMatrixToBeFiltered`

- A mxMatrix
`selectorMatrix`

- A single row or single column R matrix indicating which values should be filtered from the mxMatrix.

### Details

`omxSelectRowsAndCols`

, `omxSelectRows`

, and `omxSelectCols`

returns the filtered entries in a `mxMatrix`

specified by a single row or single column selector matrix. Each entry in the selector matrix is treated as a logical data indicating if the corresponding entry in the `mxMatrix`

should be excluded (0 or FALSE) or included (not 0 or TRUE). Typically the function is used to filter data from an `mxMatrix`

using an existence vector which specifies what data entries are missing. This can be seen in the demo: FIMLRowObjectiveBivariateCorrelation.R.

### Value

Returns a new `MxMatrix`

object with the filtered data.

### References

The function is most often used when filtering data for missingness. This can be seen in the demo: FIMLRowObjectiveBivariateCorrelation.R. The OpenMx User's guide can be found at http://openmx.psyc.virginia.edu/documentation. The `omxSelect*`

functions share some similarity to the Extract function in the R programming language.

### Examples

loadings <- c(1, -0.625, 0.1953125, 1, -0.375, 0.0703125, 1, -0.375, 0.0703125)
loadings <- matrix(loadings, 3, 3, byrow= TRUE)
loadingsMatrix <- mxMatrix("Full", free=FALSE, values=loadings, name="loadingsMatrix", byrow=TRUE)
existenceList <- c(1, 0, 1)
existenceList <- matrix(existenceList, 1, 3, byrow= TRUE)
rowsAndCols <- omxSelectRowsAndCols(loadingsMatrix, existenceList)
rows <- omxSelectRows(loadingsMatrix, existenceList)
cols <- omxSelectCols(loadingsMatrix, existenceList)