关于屏蔽功能的静音消息

我试图压制消息,解释某些功能被其他软件包掩盖.我尝试了不同的组合,但没有一个提供我需要的东西.

我的块是:

<>=
suppressPackageStartupMessages(library(doMC))
suppressPackageStartupMessages(library(aroma.affymetrix))
suppressPackageStartupMessages(library(crlmm))
suppressPackageStartupMessages(library(snpStats))
suppressPackageStartupMessages(library(pd.genomewidesnp.6))
suppressPackageStartupMessages(library(GenomicRanges))
suppressPackageStartupMessages(library(ggbio))
@ 

但是输出(我希望没有)是(在得到的PDF上):

## Loading required package:  foreach
## foreach:  simple, scalable parallel programming from Revolution Analytics
## Use Revolution R for scalability, fault tolerance and more.
## http://www.revolutionanalytics.com
## Loading required package:  iterators
## Loading required package:  parallel
## Loading required package:  R.utils
## Loading required package:  R.oo
## Loading required package:  R.methodsS3
## R.methodsS3 v1.5.2 (2013-10-06) successfully loaded.  See ?R.methodsS3 for help.
## R.oo v1.15.8 (2013-10-10) successfully loaded.  See ?R.oo for help.
##
## Attaching package:  ’R.oo’
##
## The following objects are masked from ’package:methods’:
##
##    getClasses, getMethods

有关如何解决这个问题的任何想法？