| head {SparkR} | R Documentation |
Return the first NUM rows of a DataFrame as a data.frame. If NUM is NULL, then head() returns the first 6 rows in keeping with the current data.frame convention in R.
## S4 method for signature 'DataFrame' head(x, num = 6L)
x |
A SparkSQL DataFrame |
num |
The number of rows to return. Default is 6. |
A data.frame
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; as.data.frame,
as.data.frame,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;
first, first;
groupBy, groupBy,
group_by, group_by;
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
## Not run:
##D sc <- sparkR.init()
##D sqlContext <- sparkRSQL.init(sc)
##D path <- "path/to/file.json"
##D df <- read.json(sqlContext, path)
##D head(df)
## End(Not run)