Errors using distance metric in MATLAB -

my test feature vector 'testpg' , trained feature vector 'trainpg' , both of dimension 2000*1 .i aiming find distance between 2 histogram feature vectors , hence do

distance =  norm(trainpg-testpg) 

next compare scalar threshold value check whether satisfies condition , above code works scalar value of distance ie : eg distance = 5.4 scalar

but when change code use other histogram based distance metric doesn't work

i used pdist2 function http://www.mathworks.com/matlabcentral/fileexchange/29004-feature-points-in-image--keypoint-extraction/content/fps_in_image/fps%20in%20image/help%20functions/searchingmatches/pdist2.m

the new code used is

distance = pdist2(trainpg,testpg, 'chisq') d = size(distance)

here getting subscripted assignment dimension mismatch error dimensions of distance 2000*2000 instead of 1*1

how scalar value distances?

if dimensions 2000 x 1 both of feature vectors, should do:

distance = pdist2(trainpg.',testpg.', 'chisq'); 

pdist2 considers each row different sample. need take transpose, telling matlab 2000-d feature of single example rather 1-d feature 2000 examples. side note, may want check histogram intersection distance, if feature histogram. here code.