Read & Write

Writing

(dataframe-write df path [overwrite])

writes: dataframe df as a Scheme object to path. This format preserves all types. overwrite defaults to #t.

(dataframe->csv df path [overwrite])

writes: dataframe df as a comma-separated file to path. overwrite defaults to #t.

(dataframe->tsv df path [overwrite])

writes: dataframe df as a tab-separated file to path. overwrite defaults to #t.

---

Reading

(dataframe-read path)

returns: a dataframe read from a Scheme object file at path. Types are preserved.

(csv->dataframe path [header])

returns: a dataframe read from a CSV file at path. header defaults to #t.

(tsv->dataframe path [header])

returns: a dataframe read from a TSV file at path. header defaults to #t.

---

Example

> (define df
    (make-df*
      (Boolean #t #f #t)
      (Char #\y #\e #\s)
      (String "these" "are" "strings")
      (Symbol 'these 'are 'symbols)
      (Number 1.1 2 3.2)))

> (dataframe-write df "df-example.scm")

> (dataframe-display (dataframe-read "df-example.scm"))
 ;; types are preserved
 dim: 3 rows x 5 cols
  Boolean    Char   String   Symbol  Number
   <bool>   <chr>    <str>    <sym>   <num>
       #t       y    these    these  1.1000
       #f       e      are      are  2.0000
       #t       s  strings  symbols  3.2000

> (dataframe->csv df "df-example.csv")

> (dataframe-display (csv->dataframe "df-example.csv"))
 ;; types are not preserved when reading CSV
 dim: 3 rows x 5 cols
  Boolean    Char   String   Symbol  Number
    <str>   <str>    <str>    <str>   <num>
       #t       y    these    these  1.1000
       #f       e      are      are  2.0000
       #t       s  strings  symbols  3.2000

Note

dataframe-write / dataframe-read round-trips preserve types. dataframe->csv/dataframe-tsv round-trips do not — all columns are read back as strings or numbers.