Conny Gu

Conny Gu

How to install R-extention in RapidMiner for Ubuntu?

I found the easiest way to install R extention for Ubuntun RapidMiner -> Marketplace -> R Extention RStudio -> Tools -> Install Packages… -> Input in the field “Packages”: rJava, JavaGD Or input in R Console: install.packages(c(“rJava”,”JavaGD”)) Restart RapidMiner you get a popup…

Start with R

Useful web sites for R: Quick-R R-bloggers r-tutor Kickstarting R cran.r-project.org r books Andrew Field, youtube videos Simply Statistics idre stat programiz shiny learn graph library: lattice, ggvis, ggplot2 About Package install.packages(“ggplot2”), you can also install with RStudio menu: Tools…

JAVA_HOME Problem during Hadoop installation on windows

If you install the hadoop in windows, after the installation, you will confront this problem: you can not set the evironment valuable. This file won’t work: c:\deploy\etc\hadoop\hadoop-env.cmd If you do this step: “%HADOOP_PREFIX%\sbin\start-dfs.cmd” Then you will see a error message…

Read an Image with python

If you want to read an image, you will need the ‘image’ package: import Image read the image: Image.open(filename) convert the Image to grey scale: Image.open(filename).convert(‘L’) convert the image to array: numpy.asarray(Image.open(filename).convert(‘L’)) Notice: Here is a introduction to “Image” package…

sort 2d array in python

There are many ways to sort a 2d arrays. In general, you can use the sorted(), np.array.sort(),… But you should also understand what is meaning of list1.sort(list2) ravel() vs. flatten() what return the  key function back in sorted() what will…