Returns the number of columns in a DataFrame

Description

Returns the number of columns in a DataFrame

Usage

## S4 method for signature 'DataFrame'
ncol(x)

Arguments

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; 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; head; insertInto, insertInto; intersect, intersect; isLocal, isLocal; join; limit, limit; merge, merge; mutate, mutate, transform, transform; 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

Examples

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