The general sequence of calls is shown in the simple example to help you get started. More extensive examples are provided elsewhere in the documentation.
Initialize KWFIT (first call to system) 

Clear track list (done at beginning of event) 

Set B field information (done at beginning of run) 

Set beam position and errors (done at beginning of run) 

Set beam 4momentum (done at beginning of run) 

Sets fit criteria used in KWFIT 

Sets default large vertex errors when fitting for unknown vertices 
Returns B field information 

Returns beam position and errors 

Returns beam covariance matrix 

Returns beam 4momentum 

Returns fit criteria used in all fits 

Returns information about last fit 
Create an entry in track list. No information is stored 

Delete a track 

Load CD track and its errors into track list 

Load all CD tracks and errors into track list 

Load a list of CD tracks and errors into track list 

Load secondary vertex and its errors from KNVF into track list 

Load all secondary vertices and errors from KNVF into track list 

Load secondary vertex and its errors from VFND into track list 

Load all secondary vertices and errors from VFND into track list 

kfil_track_svtf 
Load track segment and its errors from SVTF into track list 
Load all track segments and errors from SVTF into track list 

Load CCFC shower and its errors into track list 

Load all CCFC showers and errors into track list 

Load XBAL shower and its errors into track list 

Load all XBAL showers and errors into track list 

Load pizero and its errors into track list 

Load all pizeros and errors into track list 

Load QQ track into track list 

Load all QQ tracks into track list 

Load FTMONTE track and its errors into track list 

Load all FTMONTE tracks and errors into track list 
Returns number of tracks in track list 

Returns track current parameters 

Returns track unconstrained parameters 

Returns track 4momentum 

Returns track covariance matrix 

Returns actual mass of track 

Returns dca of track to point (in bend plane) 

Returns type of original list track came from (e.g., CD) 

Returns track index in original list (e.g., CD list) 

TRUE if track has a covariance matrix 

TRUE if track has position information 

TRUE if track has a fixed mass 

Returns the energy error of a track 

Returns the mass error of a track 

Returns the momentum error of a track 

kget_track_err_pperp 
Returns the pperp error of a track 
Returns the phi error of a track 

Returns the theta error of a track 

Returns error error in dca of track to point (in bend plane) 
Copy information from one track to another 

Set most information for a KWFIT track 

Set current track parameters 

Set unconstrained track parameters 

Set track covariance matrix for a track 

Set mass of a track 

Set the origin of a KWFIT track (i.e., CD list) 

Set index of track in original list (e.g., CD list) 

Set flag indicating whether or not a track has a covariance matrix 

Set flag indicating whether a track has a fixed or floating mass 

Set flag indicating whether or not a track has position information 
Set unconstrained parameters to be same as current ones 

Restore current track parameters to unconstrained ones 

ktrk_add_momentum  Add 4momentum of one track to another, ignoring position 
Move track & its covariance matrix by a fixed distance 

Move track & its covariance matrix to true PCA to a point 

Move track & its covariance matrix to PCA in bend plane to a point (CLEO definition of PCA) 

Move track & its covariance matrix to a line 

Move track & its covariance matrix to a plane 

Move track & its covariance matrix to a z position 

Move track & its covariance matrix to a particular radius 
Update all tracks from the previous fit 

Constrain a KWFIT track to a fixed 3momentum 

Constrain a KWFIT track to a fixed 4momentum 

Constrain a KWFIT track to a fixed mass 

Constrain a KWFIT track to a fixed energy 

Constrain a KWFIT track to a fixed total momentum 

Constrain a KWFIT track to come from a fixed vertex 

Constrain a KWFIT track to come from a vertex having position & errors 

Constrain 2 KWFIT tracks to be back to back, i.e., dimuon 

Constrain 2 KWFIT tracks to be back to back in CM (unboosted) frame 
Note: All vertex fitting routines have an argument which optionally allows the track parameters to be updated. If they are not updated, only the vertex and chisquare information are returned.
Find 3D vertex using line approximation. No chisquare computed. 

Find unknown 3D vertex 

Find vertex, where initial position and covariance matrix are specified 

Find vertex, incorporating beam spot information 

Force a set of tracks to pass through a single point 

kvtx_unknown_2d  Same as kvtx_unknown, except that only rphi constraint is used 
kvtx_known_2d  Same as kvtx_known, except that only rphi constraint is used 
kvtx_fixed_2d  Same as kvtx_fixed, except that only rphi constraint is used 
Find c*tau, where position and cov. matrix of starting point are specified 

Find c*tau using beam spot as starting point 

Find c*tau, where position of starting point (fixed) is specified 

kvtx_two_vertex  Find vertex given a fuzzy prod. pt. and a decay into 1 daughter + neutrals 
kvtx_two_vertex_life  Same as kvtx_two_vertex but also fit for lifetime. 
Build particle by adding 4momenta from several tracks (no constraint) 

Build particle constraining tracks to go through fixed vertex 

Build particle constraining tracks to go through known vertex with errors 

Build particle constraining tracks to go through beam spot 

Build particle constraining tracks to go through unknown vertex 

kvir_two_vertex  Build particle constraining tracks to the "twovertex" fit 
Note: All routines which manipulate W tracks use the current B field specified by kset_bfield. None of these routines use the KWFIT track list, they use only information in the argument list.
Move a W track a fixed 3D arc length 

Move a W track to true PCA to the specified point 

Move a W track to PCA in bend plane to the specified point (CLEO definition of PCA) 

Move a W track to PCA to the specified line 

Move a W track to the specified plane 

Move a W track to a particular z value 

Move a W track to the specified cylinder 

Move a W track to the specified radius 
Note: All routines which manipulate W tracks use the current B field specified by kset_bfield. None of these routines use the KWFIT track list; they use only information in the argument list.
Boost a W track from a frame moving with a specified velocity 

Boost a W track to a frame moving with a specified velocity 

Convert C track (CLEO parameters) to W format 

Convert W track to C track (CLEO parameters) 

Convert 5x5 C track covariance matrix to 7x7 W covariance matrix 

Convert 7x7 W track covariance matrix to 5x5 C covariance matrix 

kutl_origin_to_current 
Returns 3D arc length from origin to current position on W track 
kutl_distance_to_point 
Returns the 3D distance of closest approach from a W track to a point 
Returns the dca from a W track to a point (measured in bend plane) 

Returns the distance between a 3D line and a point 

Returns the distance between two 3D lines 

Finds the intersection point of two 3D lines 

kutl_vertex_approx  Find 3D vertex using line approximation. No chisquare computed. 
Finds the weighted average of two 3D vertices and returns chisquare 

Finds the chisquare for two 3D vertices to be the same 

Returns the vertex error along a specified direction 

Returns the error along line connecting two vertices 

Returns D/sigma between a track and vertex along line connecting them 

Returns the invariant mass of two W tracks 

Returns the invariant mass of three W tracks 

Returns the invariant mass of four W tracks 

Returns the 4momentum sum of two W tracks 

Returns the 4momentum sum of three W tracks 

Returns the 4momentum sum of four W tracks 