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如何使用GUI那就下这个吧

This is POLGUI Ver 1.0, a Matlab Interface for Polhemus Digitizer
Author Nitin B Bangera 

POLGUI is distributed under the terms of the GNU General Public License,
with an exception to allow for easier linking with external mesh
generators. See LICENSE.txt for more information.

Type 
help polgui_ver1_r14 on the MATLAB command prompt or read below :
-------------------------------------------------------------------------
                  -- POLGUI Ver 1.0 for Matlab R14 -- 
-------------------------------------------------------------------------
Matlab Interface for Polhemus Digitizer( Only with one stylus pen )
Author Nitin B Bangera 

NOTE : Set Screen Resolution to "1280 by 1024" or higher for GUI to be
displayed correctly

 Usage :
   

     ------ polgui_ver1_r14, by itself, creates a new POLGUI_VER1_R14 with
     default settings of 1 receivers (stylus pen)

     ------ modify line 235 to change EEG Montage 
     ------ modify line 271 and 273 to set Baud rate euivalent to that on
     Polhemus (default set to 57600)
     Baud Rate Settings on switch on back of Polhemus ( 1= UP, 0=Down)
      Baud rate    SW 1  SW 2   SW 3
        1200        0      0      0
        2400        1      0      0
        4800        0      1      0
        9600        1      1      0
        19200       0      0      1
        38400       1      0      1
        57600       0      1      1
        115200      1      1      1
Important Variables Saved: in file collected_data.mat
-------------------------------------------------------------------------
data_orig --> Original Data including the 3 consecutive points collected 
for each location for averaging and pen movement error detection
data -> Averaged data
data_transf -> Data transformed to head co-ordinate frame
location -> Names of locations digitized
count -> Total number of digitized points
M -> Rotation matrix for transformation
T -> Translation matrix
-------------------------------------------------------------------------
Description of global variables and counters in the code 

needed_loc LOC DATA DATA_ORIG DATA_TRANSF COUNTER COUNTER1 special_case strmatch_index redigitize additional T M   

needed_loc  -> chararcter array with the CARDINAL POINT locations
and EEG montage locations
LOC-> Set of digitized  locations
DATA_ORIG -> Original Data before averaging
DATA -> Data after averaging 3 successive digitizations for each point
DATA_TRANSF -> Data after co-ordinate transformation
COUNTER -> Main Counter
COUNTER1-> Counter which includes count for 3 successive digitization for each point
Tag for 4 cases for remove button : 
special_case
Case 0-> Initial Condition  , Case 1-> counter <=4
Case 2-> Counter between 4 and length of needed montage 
Case 3-> Additional Points

strmatch_index ->  matches current Vaue in the listbox with needed_loc matrix and returns index 
redigitize -> Tag to check if redigitization is needed Values: 0 or 1
additional -> Tag to check if digitization of additional points is needed Values: 0 or 1
T -> Translation Matrix
M -> Rotation Matrtix
--------------------------------------------------------------------------
Steps for head digitization using POLGUI
1.Before starting GUI, edit EEG_MONTAGE variable (on line 215 in this m-file) to set required
montage to be acquired. 

2. Start GUI by typing name of this m-file in MATLAB command line (GUI
mode) e.g. polgui_ver4_r14 


Follow these steps in GUI by clicking on respective buttons in sequential
order
a. Initialise Device: 
Serial Object created with specific Baud rate. Change this call back to
change serial port properties

To digitize position the tip of the Isotrack Stylus at the desired point
and click on the dialog box within the GUI. The co-ordinates
displayed are the averages of three sequential readings taken from the
digitizer. If they differ from each other by more than 2 mm, you are asked
to digitize the point again.

b. Get Test Point:
Secure one test point

c. Get Cardinal Points in order LA(left Auricular), RA(Right Auricular)
and Nasion.

d. Align Frame from device coordinates to head co-ordinate axes determined 
by the cardinal points
Head Coordinate system:
The head coordinate system is defined as folloew: The x axis passes through the 
preauricular points with positive values on the right, the y-axis will be
perpendicular to x axis, passing through the nasion and the positive axis 
pointing towards the nose, and the z axis will be pointed up, perpendicular to xy plane.
The auricular points are known as anatomical landmarks or cardinal points.

Principle: 
When Align Frame is press, the coordinates of the cardinal locations will 
change to head frame. Notice the z coordinates of all three points are
zero. The y coordinates of the auricular points are zero with a positive x
coordinate on the right and a negative on the left auricular point,
respectively. The nasion has  a zero x coordinate and its y coordinate is
positive. The auricular points will be almost symmetrically located: their 
x coordinates are opposite and about of equal magnitude 

-Procedure for alignment-------------------------------------------------
a1. Calculate the new origin coordinates o
Define three vectors a(nasion-la), b1(ra-la) and b2(la-ra)
Drop projection of a on b1 and b2 to calculatet1 and t2 respectively.
find ratio in which projection from b1 (point o) divides vector b1
o=la+t*b1   o=(Ox,Oy,Oz)

b1. Define the three new coordinate axes ox(normalised ra-o),oy(normalised
nasion-o),oz(cross(ox,oy))

c1. First translate orgin by -o
Define Translation matrix T as follows:
    | 1   0   0    0|
    | 0   1   0    0|
T = | 0   0   1    0|
    |-Ox -Oy -Oz   0|

d1. Then Rotate .Define Rotation Matrix M as folows:
R=[ox;oy;oz]
R1=inverse(R) or transpose(R)
   |"  "  "|
   |"  R1 "|
M= |"  "  "|
   |0  0  0|

e1. Transform points to new co-ordinate axes with center at o and three
axes ox,oy and oz
[xnew ynew znew ]=[xold yold zold 1]*T*M;
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e. Get EEG montage points.

f. Get additional points
Fot additional points , click the stylus pen for digitization.

g. Press stop to close the serial device and delete objects from memory.
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