first {SparkR}R Documentation

Return the first row of a DataFrame


Return the first row of a DataFrame

Aggregate function: returns the first value in a group.


## S4 method for signature 'DataFrame'

## S4 method for signature 'Column'



A SparkSQL DataFrame

See Also

Other DataFrame functions: $, $<-, select, select, select,DataFrame,Column-method, select,DataFrame,list-method, selectExpr; DataFrame-class, dataFrame, groupedData; [, [, [[, subset; agg, agg, count,GroupedData-method, summarize, summarize; arrange, arrange, arrange, orderBy, orderBy;,,DataFrame-method; attach, attach,DataFrame-method; cache; collect; colnames, colnames, colnames<-, colnames<-, columns, names, names<-; coltypes, coltypes, coltypes<-, coltypes<-; columns, dtypes, printSchema, schema, schema; count, nrow; describe, describe, describe, summary, summary, summary,PipelineModel-method; dim; distinct, unique; dropna, dropna, fillna, fillna, na.omit, na.omit; dtypes; except, except; explain, explain; filter, filter, where, where; groupBy, groupBy, group_by, group_by; head; insertInto, insertInto; intersect, intersect; isLocal, isLocal; join; limit, limit; merge, merge; mutate, mutate, transform, transform; ncol; persist; printSchema; rbind, rbind, unionAll, unionAll; registerTempTable, registerTempTable; rename, rename, withColumnRenamed, withColumnRenamed; repartition; sample, sample, sample_frac, sample_frac; saveAsParquetFile, saveAsParquetFile, write.parquet, write.parquet; saveAsTable, saveAsTable; saveDF, saveDF, write.df, write.df, write.df; selectExpr; showDF, showDF; show, show, show,GroupedData-method; str; take; unpersist; withColumn, withColumn; write.json, write.json; write.text, write.text

Other agg_funcs: agg, summarize; approxCountDistinct, approxCountDistinct, approxCountDistinct; avg, avg; countDistinct, countDistinct, n_distinct, n_distinct; count, n, n; kurtosis, kurtosis; last, last; max; mean; min; sd, sd, stddev, stddev; skewness, skewness; stddev_pop, stddev_pop; stddev_samp, stddev_samp; sumDistinct, sumDistinct; sum; var_pop, var_pop; var_samp, var_samp; var, var, variance, variance


## Not run: 
##D sc <- sparkR.init()
##D sqlContext <- sparkRSQL.init(sc)
##D path <- "path/to/file.json"
##D df <- read.json(sqlContext, path)
##D first(df)
## End(Not run)
## Not run: first(df$c)

[Package SparkR version 1.6.1 Index]