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--- visual3d:documentation:pipeline:expressions:reserved_names [2024/06/19 13:59] – created sgranger
+++ visual3d:documentation:pipeline:expressions:reserved_names [2025/06/20 18:45] (current) – Cleaned up page and added section headers. wikisysop
@@ Line 1: / Line 1: @@
-Visual3D Reserved Names
+====== Reserved Names ======
-===== Contents =====
+Certain names are reserved within the Visual3D pipeline/expression syntax in order to simplify common tasks.
-  * [[#CURRENT_SIGNAL|1 CURRENT_SIGNAL]]
-    * [[#Used_to_allow_multiple_signals_to_be_specified_in_an_expression|1.1 Used to allow multiple signals to be specified in an expression]]
-    * [[#Used_to_Specifying_all_signals_of_a_given_TYPE|1.2 Used to Specifying all signals of a given TYPE]]
-    * [[#APPLY_AS_SUFFIX_TO_SIGNAL_NAME|1.3 APPLY_AS_SUFFIX_TO_SIGNAL_NAME]]
-  * [[#NAN|2 NAN]]
-  * [[#isNAN|3 isNAN]]
 ===== CURRENT_SIGNAL =====
-Used to refer to a specific signal with a simple syntax
+The CURRENT_SIGNAL reserved named is used to refer to a specific signal within the input to [[visual3d:documentation:pipeline:expressions:expressions_overview|Evaluate_Expression]] with a simple syntax.
-Compute the length of one signal.
+==== Example: Compute the length of one signal ====
 The legacy syntax is:
-**Evaluate_Expression**
+<code>
+Evaluate_Expression
 /EXPRESSION=LENGTH(TARGET::ORIGINAL::RFT1)
 /RESULT_TYPES=DERIVED
@@ Line 26: / Line 19: @@
 /RESULT_NAME=_LENGTH
 /APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE
-**;**
+;
-The legacy syntax can get complicated if [[Visual3D:Documentation:Pipeline:General_Information:Pipeline_Parameters|Pipeline_Parameters]] are used in the signal name because of the order in which equations are parsed.
+</code>
+The legacy syntax can get complicated if [[Visual3D:Documentation:Pipeline:General_Information:Pipeline_Parameters|Pipeline Parameters]] are used in the signal name because of the order in which equations are parsed.
+<code>
 ! Create a pipeline parameter containing the marker name
-**Set_Pipeline_Parameter**
+Set_Pipeline_Parameter
 /PARAMETER_NAME=MARKER
 /PARAMETER_VALUE=RFT1
-**;**
+;
-**Evaluate_Expression**
+Evaluate_Expression
 /EXPRESSION=LENGTH(TARGET::ORIGINAL&:&:&::MARKER&)
 /RESULT_TYPES=DERIVED
 /RESULT_FOLDERS=PROCESSED
 /RESULT_NAME=_LENGTH
-**;**
+;
-This gets even more complicate if the folder is also a pipeline parameter.
+</code>
-An alternative is the following
+This gets even more complicate if the folder is also a pipeline parameter. An alternative is the following:
-**Evaluate_Expression**
+<code>
+Evaluate_Expression
 /EXPRESSION=LENGTH(CURRENT_SIGNAL)
 /SIGNAL_TYPES=TARGET
@@ Line 53: / Line 51: @@
 /RESULT_NAME=_LENGTH
 /APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE
-**;**
+;
-\\
+</code>
-=== Used to allow multiple signals to be specified in an expression ===
+==== Example: Specify multiple signals in an expression ====
-Compute the length of TARGETS RFT1, RFT2, and RFT3 in the ORIGINAL folder
+This example computes the length of TARGETS RFT1, RFT2, and RFT3 in the ORIGINAL folder. The legacy implementation requires a [[Visual3D:Documentation:Pipeline:Pipeline_Commands:For_Each_and_End_For_Each|For_Each]] statement:
-The legacy implementation requires a [[Visual3D:Documentation:Pipeline:Pipeline_Commands:For_Each_and_End_For_Each|For_Each]] statement
+<code>
+For_Each
-[[Visual3D:Documentation:Pipeline:Pipeline_Commands:For_Each_and_End_For_Each|For_Each]]
 /Iteration_Parameter_Name= MARKERS
 /Items= RFT1+RFT2+RFT3
-**;**
+;
-**Evaluate_Expression**
+Evaluate_Expression
 /EXPRESSION=LENGTH(TARGET::ORIGINAL&:&:&::MARKERS&)
 /SIGNAL_TYPES=TARGET
@@ Line 76: / Line 74: @@
 /RESULT_NAME=::MARKERS
 /APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE
-**;**
+;
 End_For_Each
 /Iteration_Parameter_Name=MARKERS
-**;**
+;
-Using CURRENT_SIGNAL
+</code>
+Instead, using the CURRENT_SIGNAL reserved name:
-**Evaluate_Expression**
+<code>
+Evaluate_Expression
 /EXPRESSION=LENGTH(CURRENT_SIGNAL)
 /SIGNAL_TYPES=TARGET
@@ Line 91: / Line 93: @@
 /RESULT_NAME=_LENGTH
 /APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE
-**;**
+;
-\\
+</code>
+==== Example: Specify all signals of a given type ====
-=== Used to Specifying all signals of a given TYPE ===
+This example computes the length of all TARGETS in the ORIGINAL folder. The legacy implementation requires a [[Visual3D:Documentation:Pipeline:Pipeline_Commands:For_Each_and_End_For_Each|For_Each]] command and a command to get the names of all of the TARGETS:
-Compute the length of all TARGETS in the ORIGINAL folder
+<code>
+Set_Pipeline_Parameter_To_List_Of_Signal_Names
-The legacy implementation requires a [[Visual3D:Documentation:Pipeline:Pipeline_Commands:For_Each_and_End_For_Each|For_Each]] command and a command to get the names of all of the TARGETS
-[[Visual3D:Documentation:Pipeline:Pipeline_Commands:Set_Pipeline_Parameter_To_List_Of_Signal_Names|Set_Pipeline_Parameter_To_List_Of_Signal_Names]]
 /PARAMETER_NAME=ALL_TARGETS
 /SIGNAL_TYPE=TARGET
 /SIGNAL_FOLDER=ORIGINAL
-**;**
+;
-[[Visual3D:Documentation:Pipeline:Pipeline_Commands:For_Each_and_End_For_Each|For_Each]]
+For_Each
 /Iteration_Parameter_Name= MARKERS
 /Items= ::ALL_TARGETS
-**;**
+;
-**Evaluate_Expression**
+Evaluate_Expression
 /EXPRESSION=LENGTH(TARGET::ORIGINAL&:&:&::MARKERS&)
 /SIGNAL_TYPES=TARGET
@@ Line 119: / Line 121: @@
 /RESULT_NAME=::MARKERS
 /APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE
-**;**
+;
 End_For_Each
 /Iteration_Parameter_Name=MARKERS
-**;**
+;
-Using CURRENT_SIGNAL
+</code>
+Instead, using the CURRENT_SIGNAL reserved name:
-**Evaluate_Expression**
+<code>
+Evaluate_Expression
 /EXPRESSION=LENGTH(CURRENT_SIGNAL)
 /SIGNAL_TYPES=TARGET
@@ Line 134: / Line 140: @@
 /RESULT_NAME=_LENGTH
 /APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE
-**;**
+;
-\\
+</code>
+==== Example: Apply suffix to signal name ====
-=== APPLY_AS_SUFFIX_TO_SIGNAL_NAME ===
+If the /APPLY_AS_SUFFIX_TO_SIGNAL_NAME parameter is true or if the number of result signals is the same as the number of input signals, then a suffix can be easily added for the result signal's name.
-If **APPLY_AS_SUFFIX_TO_SIGNAL_NAME** is **true**, OR RESULT_NAMES.size() == SIGNAL_NAMES.size()
+For example, when computing the length of all TARGETS in the ORIGINAL folder.
-Compute the length of all TARGETS in the ORIGINAL folder
+<code>
+Evaluate_Expression
-**Evaluate_Expression**
 /EXPRESSION=LENGTH(CURRENT_SIGNAL)
 /SIGNAL_TYPES=TARGET
@@ Line 153: / Line 159: @@
 /RESULT_NAME=_LENGTH
 /APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE
-**;**
+;
-Compute the length of Two TARGETS (RFT1 and RFT2) in the ORIGINAL folder
+</code>
+Or when computing the length of two TARGETS (RFT1 and RFT2) in the ORIGINAL folder
-**Evaluate_Expression**
+<code>
+Evaluate_Expression
 /EXPRESSION=LENGTH(CURRENT_SIGNAL)
 /SIGNAL_TYPES=TARGET
@@ Line 165: / Line 174: @@
 /RESULT_NAME=_LENGTH
 /APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE
-**;**
+;
-Compute a Best_Plane_Fit for multiple signals at each frame of data
+</code>
-**Evaluate_Expression**
+Also when calculating a Best_Plane_Fit for multiple signals at each frame of data.
+<code>
+Evaluate_Expression
 /EXPRESSION=Best_Fit_Plane(CURRENT_SIGNAL)
 /SIGNAL_TYPES=TARGET
@@ Line 177: / Line 189: @@
 /RESULT_NAME=LSK_PLANE
 /APPLY_AS_SUFFIX_TO_SIGNAL_NAME=TRUE
-**;**
+;
-\\
+</code>
-If **APPLY_AS_SUFFIX_TO_SIGNAL_NAME** is **false**, AND RESULT_NAMES.size() == 1
-Compute the length of one TARGET (TARGET::ORIGINAL::RFT1)
-**Evaluate_Expression**
-/EXPRESSION=LENGTH(TARGET::ORIGINAL::RFT1)
-/RESULT_TYPES=DERIVED
-/RESULT_FOLDERS=PROCESSED
-/RESULT_NAME=RFT1_LENGTH
-**;**
 ===== NAN =====
-NAN is a reserved string used to designate "Not a Number".
+NAN is a reserved string used to designate "Not a Number". Visual3D commands refer to [[Visual3D:Documentation:C3D_Signal_Types:DATA_NOT_FOUND|NO_DATA or DATA_NOT_FOUND]] as NAN.
-Visual3D commands refer to [[Visual3D:Documentation:C3D_Signal_Types:DATA_NOT_FOUND|NO_DATA or DATA_NOT_FOUND]] as NAN
+For example, the expression 1/0 results in NAN.
-For example, the expression 1/0 results in NAN
+==== isNAN function ====
-===== isNAN =====
-isNAN(expression) tests values against NAN - If the number is NAN the result is 1, otherwise the result is 0
+The function isNAN(expression) tests values against NAN - If the number is NAN the result is 1, otherwise the result is 0.
-[Set_Pipeline_Parameter_From_Expression]
+<code>
+Set_Pipeline_Parameter_From_Expression
 /PARAMETER_NAME= NAN_TEST
 /EXPRESSION=ISNAN(1/0)
 /AS_INTEGER=TRUE
-**;**
+;
 ::NAN_TEST = 1
-[Set_Pipeline_Parameter_From_Expression]
+Set_Pipeline_Parameter_From_Expression
 /PARAMETER_NAME= NAN_TEST
 /EXPRESSION=ISNAN(-999999.000000)
 /AS_INTEGER=TRUE
-**;**
+;
-::NAN_TEST = 1
-Returns "1" because -999999 is equal to Data Not Found in Visual3D.
-[Set_Pipeline_Parameter_From_Expression]
+::NAN_TEST = 1 ! Returns "1" because -999999 is equal to Data Not Found in Visual3D.
+Set_Pipeline_Parameter_From_Expression
 /PARAMETER_NAME= NAN_TEST
 /EXPRESSION=ISNAN(15)
 /AS_INTEGER=TRUE
-**;**
+;
 ::NAN_TEST = 0
-Example: Set negative values to NO_DATA
+</code>
+==== Example: Set negative values to NO_DATA ====
-If the z-component of the LELB signal is below 0 set the frame to NO_DATA
+In this example, if the z-component of the LELB signal is below 0 then we will set the frame to NO_DATA.
-**Evaluate_Expression**
+<code>
+Evaluate_Expression
 /EXPRESSION=(TARGET::ORIGINAL::LELB::Z>0)/(TARGET::ORIGINAL::LELB::Z>0)*TARGET::ORIGINAL::LELB
 /RESULT_NAME=LELB
 /RESULT_TYPE=TARGET
 /RESULT_FOLDER=PROCESSED
-**;**
+;
+</code>
+===== ORIGIN =====
+Internally Visual3D specifies the location ORIGIN. To avoid confusion, this string cannot be used to name either a TARGET or a LANDMARK.