modifyWeights {limma} | R Documentation |

## modifyWeights

### Description

Modify weights matrix for given gene status values.

### Usage

modifyWeights(weights, status, values, multipliers)

### Arguments

`weights` |
numeric matrix of relative weights, rows corresponding to genes and columns to arrays |

`status` |
character vector giving the control status of each spot on the array, of same length as the number of rows of `weights` |

`values` |
character vector giving subset of the unique values of `status` |

`multipliers` |
numeric vector of same length as `values` giving factor by which weights will be modified |

### Details

The function is usually used to temporarily modify the weights matrix during normalization of data.
The function can be used for example to give zero weight to spike-in ratio control spots during normalization.

### Value

Numeric matrix of same dimensions as `weights`

with rows corresponding to `values`

in `status`

modified by the specified multipliers.

### Author(s)

Gordon Smyth

### See Also

An overview of normalization functions available in LIMMA is given in 05.Normalization.

### Examples

w <- matrix(runif(6*3),6,3)
status <- c("Gene","Gene","Ratio_Control","Ratio_Control","Gene","Gene")
modifyWeights(w,status,values="Ratio_Control",multipliers=0)

[Package

*limma* version 2.4.7

Index]