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ssGetDataTypeFixedExponent

Return exponent of slope of registered data type

Syntax

extern int ssGetDataTypeFixedExponent (SimStruct *S, DTypeId
                                       dataTypeId)

Arguments

S

SimStruct representing an S-function block.

dataTypeId

Data type ID of the registered data type for which you want to know the exponent.

Description

Fixed-point numbers can be represented as

real-world value = (slope × integer) + bias,

where the slope can be expressed as

slope = fractional slope × 2exponent.

This function returns the exponent of a registered fixed-point data type:

  • For power-of-two scaling, the exponent is the negative of the fraction length.

  • If the data type has trivial scaling, including for data types single and double, the exponent is 0.

  • If the registered data type is ScaledDouble, the exponent returned is that of the nonoverridden data type.

This function errors out when ssGetDataTypeIsFxpFltApiCompat returns FALSE.

Requirement

To use this function, you must include fixedpoint.h and fixedpoint.c. For more information, see Structure of the S-Function.

Languages

C

TLC Functions

FixPt_DataTypeFixedExponent

Version History

Introduced before R2006a