spark dataframe to pairedRDD in Scala -
i new spark , want convert dataframe pairedrdd. dataframe looks like:
tagname,value,minute tag1,13.87,5 tag2,32.50,10 tag3,35.00,5 tag1,10.98,2 tag5,11.0,5
i want pairedrdd(tagname, value). tried
val bykey:map[string,long] = winowfiverdd.map({case (tagname,value) => (tagname)->value})
i getting following error:
error: constructor cannot instantiated expected type
help appreciated. in advance.
i'd use dataset.as
:
import org.apache.spark.rdd.rdd val df = seq( ("tag1", "13.87", "5"), ("tag2", "32.50", "10"), ("tag3", "35.00", "5"), ("tag1", "10.98", "2"), ("tag5", "11.0", "5") ).todf("tagname", "value", "minute") val pairedrdd: rdd[(string, double)] = df .select($"tagname", $"value".cast("double")) .as[(string, double)].rdd
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