TdmsSlice Supported Formats

Broad TDMS data type support, with clear limits.

TdmsSlice supports common numeric TDMS data as well as String, Timestamp, Complex, and DAQmx Raw Data for Quick Preview and/or CSV export.

Evaluation and Standard use the same supported data types and the same core reading behavior.

Data type support

Quick Preview and CSV export are separate capabilities. Some data types can be exported correctly even when a waveform preview is not meaningful or intentionally not provided.

TDMS DataType Quick Preview CSV Export Notes
DoubleFloat ✓ Supported ✓ Supported
SingleFloat ✓ Supported ✓ Supported
DoubleFloatWithUnit ✓ Supported ✓ Supported Unit metadata retained where available
SingleFloatWithUnit ✓ Supported ✓ Supported Unit metadata retained where available
Int8 / Int16 / Int32 / Int64 ✓ Supported ✓ Supported
Uint8 / Uint16 / Uint32 / Uint64 ✓ Supported ✓ Supported
Boolean ✓ Supported ✓ Supported Boolean meaning is preserved; CSV values are True / False
String — Not available ✓ Supported Exported as text; not converted to numeric values
Timestamp — Not available ✓ Supported Raw Timestamp Channel values are exported as ISO 8601 UTC
ComplexSingleFloat / ComplexDoubleFloat — Not available ✓ Supported Real and Imaginary values are exported in separate CSV columns
DAQmx Raw Data ✓ Supported ✓ Supported Uses npTDMS scaling-applied values

“Supported” describes the current TdmsSlice product path. It does not mean every possible combination of TDMS raw type, scaling type, scope, and file structure has been exhaustively tested.

Why are some types CSV-only?

String, raw Timestamp, and Complex Channels are valid data sources, but TdmsSlice does not force them into an artificial waveform preview.

You can still select a sample-index range and export the Channel to CSV. String values stay as text, Timestamp values are exported as ISO 8601 UTC, and Complex values are written as separate Real and Imaginary columns.

DAQmx Raw Data

TdmsSlice supports Quick Preview and CSV export for DAQmx Raw Data using the scaling-applied values returned by npTDMS.

The initial release does not expose raw scaler values or add a raw/scaled switching interface.

Not supported in the initial release

TdmsSlice stops or disables value operations when a path is not supported rather than presenting data as if it had been read correctly.

  • String waveform Quick Preview
  • ExtendedFloat data
  • FixedPoint data
  • Automatically joining a raw Timestamp Channel to a separate value Channel
  • Exporting DAQmx raw scaler values or switching between raw and scaled output

Metadata may still be available

If a TDMS object can be opened for metadata but its value type is not supported for Preview or CSV, TdmsSlice may still show its metadata while disabling unsupported value operations.

TdmsSlice does not treat “npTDMS can read it” as the same thing as “TdmsSlice supports it through the product workflow.”

Structures used in product-path validation

Validation has included public TDMS files and purpose-built fixtures covering several structures that are less common than a simple single-segment numeric file.

Native Complex Single / Double data
DAQmx Raw Data with Polynomial or Linear Scaling
True TDMS interleaved DAQmx Raw data
Big-endian Double data
Files with many TDMS segments
Metadata-only objects and RawIndex reuse

Real TDMS files vary. The most reliable compatibility check is to use Evaluation with the files you actually work with before purchasing Standard.