| name | simulink-single-precision-conversion |
| description | Converts a double-precision Simulink system or subsystem to single precision using DataTypeWorkflow.Single (Fixed-Point Designer). The single conversion replaces all user-specified double-precision data types, as well as output data types that compile to double precision, with single-precision data types. Use this skill when converting Simulink systems to single precision, reducing memory usage of a Simulink system, optimizing for embedded targets. Do NOT use for standalone MATLAB .m code single conversion. |
| license | MathWorks BSD-3-Clause |
| metadata | {"author":"MathWorks","version":"1.7"} |
Single-Precision Conversion for Simulink Models (Fixed-Point Designer)
Toolbox: Fixed-Point Designer
Function: DataTypeWorkflow.Single.convertToSingle
Converts user-specified double-precision data types — across block settings, Stateflow chart
settings, signal objects, and bus objects — to single precision. Boolean, built-in integer
(int8, uint8, int16, …), and fixed-point types are left unchanged.
When to Use
- Converting a Simulink model (
.slx) or subsystem from double-precision to single-precision
- Reducing memory footprint for embedded hardware with native single-precision support
- Batch/CI conversions, checking conversion compatibility, or verifying no stowaway doubles remain
- Summarizing the single conversion compatibility report and conversion result for the user in plain language
When NOT to Use
- Standalone MATLAB
.m code — use the convertToSingle function with coder.config('single') instead
- Fixed-point data type optimization — use
DataTypeWorkflow.Converter instead
Public API
ConversionReport = DataTypeWorkflow.Single.convertToSingle(systemToConvert)
systemToConvert (char) — full block path of the loaded model or subsystem (e.g. 'myModel' or 'myModel/Controller').ConversionReport (struct) — compatibility check, converted items, and verification status (see field tables below).
Worked example: openExample("fixedpoint/ConvertSystemToSinglePrecisionExample")
Rules
- Open with
open_system(modelName), not load_system — the user must see the diagram before/after.
- Never call
save_system — saving destroys the double-precision baseline and blocks meaningful re-runs. Leave the model dirty; persist only if the user explicitly asks.
- The compatibility check runs inside
convertToSingle; read its results from report.CheckInfo (it is not a separate call).
- Get the user's explicit consent before converting. If the model path, subsystem, or scope is ambiguous, ask.
- Always inspect
report.VerifyInfo.StowawayDblBlks afterward — remaining stowaway doubles mean the conversion is incomplete.
- Assign the report to a local variable (
report = ...;) — don't pollute the base workspace or echo the raw struct.
Report Structure
The tool runs check → convert → verify, populating three sub-structs on the report.
report.CheckInfo
| Field | Description |
|---|
ready | Logical — true if the system can be converted |
err | Error info (empty on success) |
IncompatibleBlks | Blocks not supporting single precision |
UnsupportedBlks | Blocks unsupported by the conversion tool (with ErrorMsgs) |
DTLockedDblBlks | Blocks with locked double data types (do not block conversion) |
StowawayDblBlks | Blocks generating double operations found during the check |
TLSSettings | Models whose Target Language Standard was updated to C99 |
DTOSettings | Systems whose Data Type Override was reset |
SolverSettings | Models whose variable-step solver was changed to fixed-step |
configSettings | Config params updated (e.g. GenerateComments, ParameterPrecisionLossMsg) |
memoryUse.BeforeValue | Per-parameter memory table; column RuntimeMemory (bytes) before conversion |
report.ConvertInfo
Records what the converter actually did.
| Field | Description |
|---|
ready | Logical — true if the convert step ran cleanly |
err | Error info; empty ([]) on success |
results | Cell array of fxptds.BlockResult — the blocks/signals changed from double to single |
report.VerifyInfo
| Field | Description |
|---|
StowawayDblBlks | Blocks still generating double operations after conversion |
memoryUse.AfterValue | Per-parameter memory table; column RuntimeMemory (bytes) after conversion |
The check phase validates the Target Language Standard, Data Type Override, incompatible
blocks, stowaway doubles, data-type-locked doubles, and solver settings — and auto-updates
several of them. The tool handles TLS→C99, DTO cleanup, and solver changes automatically;
you do not need to set these manually. See references/edge-cases.md
for the full auto-update behavior, error identifiers, and edge cases:
- Model not loaded / invalid path (
Simulink:Commands:InvSimulinkObjectName); update-diagram failures (DataTypeWorkflow:Single:UpdateDiagramFailed)
- Incompatible blocks (continuous blocks, MATLAB System blocks) and unsupported MATLAB Function Blocks (globals, MCOS classes, Simulink function calls)
- Auto-updates (TLS, DTO, solver, config), model-reference scope handling, idempotency, and cleanup on model close
Generating the Conversion Report
After convertToSingle returns, summarize the result for the user in plain language — do not
dump the raw struct. Put the exact API call used at the top for traceability.
For the required output sections, empty-report fallback, reporting conventions, and the
Embedded Coder readiness-check follow-up, see references/reporting-format.md.
Prerequisites & Limitations
- Requires MATLAB, Simulink, and Fixed-Point Designer; the model must be loaded.
- The conversion engine is a singleton — only one conversion session can be active at a time.
- MATLAB Function Blocks with complex logic and model references may need individual review — see references/edge-cases.md.
Copyright 2026 The MathWorks, Inc.
