Like variables, the parameter functions are split into function = groups.

=20
=20

Functions in this group all return a time, either in seconds or normaliz=
ed to percent if you specify the **Time Normalize Between** ev=
ents.

**Event A.**The time of A.**Event A to Event B.**The duration from A to B.**Variable A max value [Event A, Event B].**The time when= variable A attains its maximum value between two events of type A and B.**Variable A min value [Event A, Event B].**As above, but= for the minimum value.**Variable A crossing Value going up [Event A, Event B].**= The time of variable A crossing a Threshold value on the way up, between t= wo events of type A and B.**Variable A crossing Value going down [Event A, Event B]. As above, but crossing the threshold going down.**

These functions calculate the total time a variable fulfils a certain co= ndition.

**Above Value [Event A, Event B].**The total time a varia= ble is above a certain threshold value, in seconds, between events A and B.=**Below Value [Event A, Event B].**As above, but the time= the variable is below the threshold value.

This group contains only one function.

**[Event A, Event B]**, this calculates how often the even= t pair A and B occurs. This could, for example, be used to calculate cadenc= e, which is the step frequency, by specifying event A as**foot strik= e**and B as**foot off**. Although the standard unit f= or frequency is Hz, you can also choose units such as steps/min.

These functions calculate the value of a variable, or the value of a com= bination of variables, at specific points in time.

**Variable A [Event A].**Simply the value of the variable= at the time specified by the event.**Variable A [Event A] + Variable B [Event B].**The two v= ariable values added together, the values taken at the points in time speci= fied by events A and B, respectively.**Variable A [Event A] =E2=80=93****Variable B [Even= t B].**Variable B subtracted from A.**Variable A range [Event A, Event B].**Variable A=E2=80= =99s range (that is, its minimum value subtracted from its maximum value) f= or the time span defined by events A and B.**Variable A max [Event A, Event B].**Variable A=E2=80=99= s maximum value for the time span defined by events A and B.**Variable A min [Event A, Event B].**As above, except fo= r Variable A=E2=80=99s minimum value.

This group contains only one function.

**Variable A [Event A, Event B],**calculates the integral= over the time span defined by events A and B.

This stands for =E2=80=9Croot mean square=E2=80=9D, which adds up the sq= uare of all sample points and finally returns the square root of the sum.

**Variable A [Event A, Event B].**Calculates the RMS of v= ariable A between the events A and B.**Variable A =E2=80=93****Variable B [Event A, Event= B].**Calculates the RMS of the difference between variables A and = B over the time span defined by events A and B.

These functions calculate the average value of a variable, or a combinat= ion of variables.

**Variable A [Event A, Event B].**The average of each sam= ple point over the time span defined by events A and B.**Variable A=E2=80=99s local coordinates in Variable B [Event A, = Event B].**Variable A can be either a point or a segment, whereas v= ariable B has to be a segment. The function calculates the average position= (and, if a segment, orientation) of A in B=E2=80=99s reference frame. The = main use of this function is to store an anatomical point or segment in a t= echnical segment=E2=80=99s reference system based on a static trial, which = can be used later in a dynamic trial.

Equivalent to the average function above, except that it calculates the = standard deviation.

- Only
**Variable A [Event A, Event B]**is available.

Functions in this group calculate parameters based on 3D variables.

**Distance Variable A [Event A] to Variable B [Event B]. Calculates the straight-line distance from the 3D variable A to the 3D var= iable B.****Speed Variable A [Event A, Event B].**Calculates the sp= eed of 3D variable A between event A and event B. This corresponds to the d= istance covered divided by the time between the two events.**Distance Travelled Variable A [Event A, Event B].**Calc= ulates the 3D distance traveled by variable A between events A and B. This = is calculated by adding each line segment traveled for each frame between t= he two events.

These are special functions for calculating typical temporal parameters.=

**Single Support [Event A, Event B] =E2=80=93 [Event C, Event D].=**Calculates the time between events A and B, but then subtracts th= e time*outside*the span defined by event C to event D, should eith= er of these lie inside the A to B span. When A =3D ipsilateral foot contact= , B =3D ipsilateral foot off, C =3D contralateral foot off and D =3D contra= lateral foot contact, single support is calculated as the total stance time= (A to B) minus the time of double support (A to C and D to B). However, sh= ould C and D lie outside the span A to B (for example when a running motion= is analyzed), nothing is subtracted since there is no double support.**Double Support [Event A, Event B] =E2=80=93 [Event C, Event D].=**Calculates the time from event A to event B minus the time*in= side*the span defined by event C to event D.

These functions enable you to combine other parameters.

**Parameter A + Parameter B.**Adds two parameters.**Parameter A =E2=80=93****Parameter B.**Sub= tracts parameter B from parameter A.**Parameter A * Parameter B.**Multiplies the two paramete= rs.**Parameter A / Parameter B.**Divides parameter A with B.=**(Parameter A + Parameter B) / 2.**Takes the average of = two parameters.