write_csv
The write_csv method will write a table to a standard CSV file.
Syntax
write(table: Table, path: str, cols: list[str])
The deephaven package's write_csv method is identical in function to deephaven.csv.write; however, write_csv is the preferred method as it differentiates the method from deephaven.parquet.write.
Parameters
| Parameter | Type | Description |
|---|---|---|
| table | Table | The table to write to file. |
| path | str | Path name of the file where the table will be stored. |
| cols optional | list[str] | The source column(s) to include in the CSV file. The default value is all source columns. |
Returns
A CSV file located in the specified path.
Examples
Deephaven writes files to locations relative to the base of its Docker container. See Docker data volumes to learn more about the relation between locations in the container and the local file system.
In the following example, write_csv writes the source table to /data/output.csv. All columns are included.
from deephaven import new_table
from deephaven.column import string_col, int_col
from deephaven import write_csv
from deephaven.constants import NULL_INT
source = new_table(
[
string_col("X", ["A", "B", None, "C", "B", "A", "B", "B", "C"]),
int_col("Y", [2, 4, 2, 1, 2, 3, 4, NULL_INT, 3]),
int_col("Z", [55, 76, 20, NULL_INT, 230, 50, 73, 137, 214]),
]
)
write_csv(source, "/data/output.csv")
- source
In the following example, only the columns X and Z are written to the output file.
from deephaven import new_table
from deephaven.column import string_col, int_col, double_col
from deephaven import write_csv
from deephaven.constants import NULL_INT
source = new_table(
[
string_col("X", ["A", "B", None, "C", "B", "A", "B", "B", "C"]),
int_col("Y", [2, 4, 2, 1, 2, 3, 4, NULL_INT, 3]),
int_col("Z", [55, 76, 20, NULL_INT, 230, 50, 73, 137, 214]),
]
)
write_csv(source, "/data/output.csv", cols=["X", "Z"])
- source