About this blog
This blog is mostly about my pursuits in Data Science. Previous blog entries also dealt with storage, compute, virtualization and professional services. Currently the focus is on Data Science, including Big Data, Hadoop, Business Intelligence, Data Warehouse, Data Integration and Visualization. From time to time I will blog about other things of interest. The opinions expressed in this blog are entirely my own and should not be taken as the opinion of my employer.
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Tag Archives: hadoop
Changing key/value split delimiter in Hadoop .20.2
You can find a list of deprecated properties in Hadoop .20.2 here: http://hadoop.apache.org/docs/r2.0.3-alpha/hadoop-project-dist/hadoop-common/DeprecatedProperties.html After reading this you may think that you need to set mapreduce.input.keyvaluelinerecordreader.key.value.separator in order to change the delimiter for the KeyValueTextInputFormat. However, what I have noticed from experience … Continue reading
Changing MapReduce number of Mappers in Hadoop .20.2
In earlier releases of Hadoop you could change the number of mappers by setting: setNumMapTasks() You did this using JobConf. Things in Hadoop .20.2 have migrated to using the Job class instead of JobConf. Although setNumReduceTasks() is still valid, setNumMapTasks() … Continue reading
Apache Mahout prepare20newsgroups in version .7
Apache Mahout has gone through some changes recently, and one of the things you will notice no longer works, is the old prepare20newsgroups classifier routine. This has been replaced, and the new syntax is much different. This page will walk … Continue reading