SoDataMeasureCustom Class Reference
[Measures]

class to define a custom measure. More...

#include <ImageViz/Nodes/Measures/SoDataMeasureCustom.h>

Inheritance diagram for SoDataMeasureCustom:

List of all members.

Public Member Functions
virtual SoType	getTypeId () const
	SoDataMeasureCustom ()
virtual const SbString &	getMeasureName () const
virtual UnitDimension	getUnitDimension () const
virtual ResultFormat	getFormat () const
Static Public Member Functions
static SoType	getClassTypeId ()
Public Attributes
SoSFString	measureName
SoSFString	formula

---

Detailed Description

class to define a custom measure.

A custom measure is defined by a string formula that can use other custom or predefined measure. It must have a unique name.

     // Example of code to define a custom measure using two predefined measure and
     // defined as the ratio of the Volume/Area.
     SoDataMeasureCustom* myMeasure1 = new SoDataMeasureCustom();
     myMeasure1->measureName = "myMeasure1";
     myMeasure1->formula = SoDataMeasurePredefined::getName(SoDataMeasurePredefined::VOLUME) + "/" + SoDataMeasurePredefined::getName(SoDataMeasurePredefined::AREA);

     // myMeasure1 can in turn be used to define an other custom measure, define as 2*myMeasure1
     SoDataMeasureCustom* myMeasure2 = new SoDataMeasureCustom();
     myMeasure2->measureName = "myMeasure2";
     myMeasure2->formula = myMeasure1.getMeasureName() + "*2";

Custom formula syntax

Custom formula syntax is checked before acceptation by ImageViz. Custom measure formula and custom filter formula follow the same basic rules and can use the same set of predefined functions. Custom measure formula must be a numerical value whereas custom filter formula must be a logical value to be accepted. Formula can be composed of constants, operators, functions and variables (native measures and custom measures).


Remarks :

• The following (unless specified) constants, operators, functions and variables are unsensitive to case and can be used both with custom measures and custom filters.
• The following (unless specified) operators and functions are unsensitive to spaces. Constants and variables must not be directely attached to alpha numerical symbols.


The following syntax can be used to define a formula :

Basic operators

() : brackets allowing to group elements and to modify operators precedence
example : (2 + 3)*4

+ : unary arithmetic operator [plus]
example : + a

- : unary arithmetic operator [minus]
example : - b

+ : binary arithmetic operator [plus]
example : a + b

- : binary arithmetic operator [minus]
example : a - b

* : binary arithmetic operator [multiply]
example : a * b

/ : binary arithmetic operator [divide]
example : a / b
remark : a division by 0 returns the value 0 in order to avoid exceptions.

** : binary arithmetic operator [pow]
example : a ** b

! : unary logical operator [not]
example : !(a>b)

&& : or And : binary logical operator [and]
example : (a>b) && (a<c)
example : (a>c) And (a<c)
remark : And : operator must not be directely attached to alpha numerical symbols.

|| : or Or : binary logical operator [or]
example : (a>b) || (a<c)
example : (a>b) Or (a<c)
remark : Or : operator must not be directely attached to alpha numerical symbols.

== : comparison operator (logical and arithmetic) [equal]
example : a==b
example : true==true

!= : comparison operator (logical and arithmetic) [different]
example : a != b
example : true != false

< : arithmetic comparison operator [strictly inferior]
example : a < b

<= : arithmetic comparison operator [less]
example : a<= b

> : arithmetic comparison operator [strictly superior]
example : a > b

>= : arithmetic comparison operator [superior]
example : a >= b

Constant values

Pi : , the pi constant
example : 3 * Pi

E : , the Euler's constant
example : 2 * E

True : the true boolean value
example : (3<Pi)==True

False : the false boolean value
example : (3>Pi)==False

NbFeret : distribution size for feret measures
example : 3*NbFeret

gx : , gy : and gz : image X, Y and Z size associated to measure
example : 3*gx
remark : not available for custom filters

cx : , cy : and cz : stand for pixel real size according to calibration
example : 3*cx
remark : not available for custom filters

Functions

Abs : absolute value of a numerical value
example : abs(a)

Sqrt : square root value of a numerical value
example : sqrt(a)
remark : a must be positive or null

Exp : exponential value of a numerical value
example : exp(a)

Log : natural logarithm value of a numerical value
example : log(a)
remark : a must be strictly positive

Cos : cosine value of a numerical value
example : cos(a)

Sin : sine value of a numerical value
example : sin(a)

Tan : tangent value of a numerical value
example : tan(a)

ACos : arccosine value of a numerical value
example : acos(a)
remark : a must within range [-1, 1]

ASin : sine arcvalue of a numerical value
example : asin(a)
remark : a must within range [-1, 1]

ATan : arctangent value of a numerical value
example : atan(a)

ATan2 : arctangent value of a 2d point
example : atan(y, x)

CosH : hyperbolic cosine value of a numerical value
example : cosh(a)

SinH : hyperbolic sine value of a numerical value
example : sinh(a)

TanH : hyperbolic tangent value of a numerical value
example : tanh(a)

Min : retrieve minimum value of a variable sized set of numerical values
example : min(a, b, c, d)

Max : retrieve maximum value of a variable sized set of numerical values
example : max(a, b, c, d, e)

Avg : retrieve mean value of a variable sized set of numerical values
example : avg(a, b, c)

Median : retrieve median value of a variable sized set of numerical values
example : median(a, b, c, d)

Sum : compute the sum of a variable sized set of numerical values
example : sum(a, b, c)

Sum : compute the product of a variable sized set of numerical values
example : product(a, b, c, d, e)

If : : conditional evaluation of an expression
example : if(predicat, value_true, value_false)
remark : Each member of a conditional expression is systematically evaluated even if it is not supposed to be reached by the condition. Thus an instruction can raise an error even if the condition is supposed to prevent invalid evaluations.
example: if(I1<=0, 0, log(I1)) will raise an error if a voxel value is lower or equal to 0 since the log expression will be evaluated before the if statement.

SEE ALSO

SoDataMeasurePredefined, SoLabelAnalysisQuantification, SoFilterAnalysisQuantification, SoGlobalAnalysisQuantification, SoFilterByMeasureProcessing, SoSieveLabelingProcessing, SoAdaptiveThresholdingProcessing

See related examples:

CustomMeasure

---

Constructor & Destructor Documentation

SoDataMeasureCustom::SoDataMeasureCustom

(

)

Default constructor.

---

Member Function Documentation

static SoType SoDataMeasureCustom::getClassTypeId

(

)

[static]

Returns the type identifier for this class.

Reimplemented from SoDataMeasure.

virtual ResultFormat SoDataMeasureCustom::getFormat

(

)

const [virtual]

Returns the "result format" of the result data. . Default is FLOAT

Implements SoDataMeasure.

virtual const SbString& SoDataMeasureCustom::getMeasureName

(

)

const [inline, virtual]

Returns the name of this measure. This name can be then used in custom measure formula

Implements SoDataMeasure.

virtual SoType SoDataMeasureCustom::getTypeId

(

)

const [virtual]

Returns the type identifier for this specific instance.

Reimplemented from SoDataMeasure.

virtual UnitDimension SoDataMeasureCustom::getUnitDimension

(

)

const [virtual]

Returns the "unit dimension" of the result data. . Default is NOUNIT

Implements SoDataMeasure.

---

Member Data Documentation

SoSFString SoDataMeasureCustom::formula

Formula describing the custom measure.

SoSFString SoDataMeasureCustom::measureName

Measure name that can be used in custom measure combination formula.

---

The documentation for this class was generated from the following file:

• ImageViz/Nodes/Measures/SoDataMeasureCustom.h