Column Drop By Index

Drop selected zero-based columns from a rectangular CSV, preserving all remaining cells and rejecting removal of every column.

Description

Dropping CSV columns removes fields by position while preserving the surviving records.

Dropping CSV columns removes fields by position while preserving the surviving records. Column positions here start at zero, so index 0 refers to the first field, including its header if one is present.^[1]

Drop selected zero-based columns from a rectangular CSV, preserving all remaining cells and rejecting removal of every column.

When to use Column Drop By Index

Use this tool to drop selected zero-based columns from a rectangular CSV, preserving all remaining cells and rejecting removal of every column.

Choose the original CSV text, decoded cell strings, byte values or counts requested by this tool. Use the stated delimiter, encoding, indexing and number/date convention.

How to use Column Drop By Index and understand its results

Choose the original CSV text, decoded cell strings, byte values or counts requested by this tool. Use the stated delimiter, encoding, indexing and number/date convention.
Enter csv, delimiter, indices using the field table and calculation rules, then run the tool.
Read csv. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
csv	CSV text	string; maximum length: 100000	Required
delimiter	Delimiter	string; one of ,, ;,	Required
indices	Indices	list of integer; minimum: 0; minimum entries: 0; maximum entries: 10000	Required

Supply complete CSV text, its comma, semicolon or tab delimiter, and the indices to remove. The parser decodes quoted fields and checks that all records have equal widths. Repeated indices are treated as one removal; out-of-range indices and removing every column from a nonempty table are errors. Every record is projected onto the remaining columns and serialized with the chosen delimiter, doubled interior quotes and LF record separators. Empty CSV with no indices returns empty text.

kept columns = original columns minus the set of requested zero-based indices

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
csv	CSV text	string

json

{
  "input": {
    "csv": "id,name,age\n1,Ada,36",
    "delimiter": ",",
    "indices": [
      2
    ]
  },
  "output": {
    "csv": "id,name\n1,Ada"
  }
}

Limitations and assumptions

This rewrites CSV spelling: original quoting, record-ending style and a terminal newline are not preserved. It does not identify headers, read files, or infer column names. Embedded newlines remain field content. Parsing is limited to 10,000 total fields.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Extremely large text inputs are rejected. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use RFC 4180 Quoted Field Parser Check: Check RFC 4180 field quoting with explicit Unicode and CR/LF extensions; blank records are retained, and field-width consistency is checked separately. For a complementary task, use Cell Length Min/Max Per Column: Measure minimum and maximum Unicode code-point lengths of decoded data cells per column, including empty strings and excluding an explicit header; zero observations return count zero.

References

Column Drop By Index — tool.io

Similar or alternative tools

RFC 4180 Quoted Field Parser Check
Check RFC 4180 field quoting with explicit Unicode and CR/LF extensions; blank records are retained, and field-width consistency is checked separately.
Cell Length Min/Max Per Column
Measure minimum and maximum Unicode code-point lengths of decoded data cells per column, including empty strings and excluding an explicit header; zero observations return count zero.