Problem#1: Caused by: java.lang.ClassNotFoundException: org.apache.spark.SparkConf while running "mahout spark-rowsimiliarity" command. spark version 2.3_for_hadoop2.7, hadoop version 2.6.5, mahout version 0.13.
Soln: downloaded spark 2.3_for_hadoop_2.6.. didnt woked,
source:stackoverflow
git clone http://github.com/apache/mahout
cd mahout
mvn clean package -Dspark.version=2.1.0 -Dscala.version=2.11.8 -Dscala.compat.version=2.11
Problem#2: "mahout spark-rowsimilarity" ended in error Caused by: java.lang.ClassNotFoundException: scopt.OptionParser
Soln: Downloaded scopt_2.10-3.2.0.jar from mvn repo. and used as below
CLASSPATH=$CLASSPATH:scopt_2.10-3.2.0.jar mahout spark-rowsimilarity --input /home/<USER>/projects/mahout/input/input_products.csv --output /tmp/output_rv