do this code return the minimum assignment or the max one?

[zhuzy-2018]

sometimes i get the max return:
d2: -0.851823 -0.0848411 0.997337
0.519324 0.752464 0.05258
0.971547 0.304817 -0.311632
dd: -1 -1 0
-1 0 -1
0 -1 -1
pair 0 is :0,2
pair 1 is :1,1
pair 2 is :2,0

sometimes i get the min one:
d2: 0.0511896 -0.0754626 -0.831758
0.541599 0.0293286 -0.483856
0.436718 -0.553582 0.285733
dd: -1 -1 0
0 -1 -1
-1 0 -1
pair 0 is :0,2
pair 1 is :1,0
pair 2 is :2,1

why is that? and how can i fix that?

[Gluttton]

Hello @zhuzy-2018,

-0.851823 -0.0848411 0.997337
0.519324 0.752464 0.05258
0.971547 0.304817 -0.311632

Please note that the algorithm requires as input parameters a nonnegative cost matrix (https://en.wikipedia.org/wiki/Hungarian_algorithm#The_problem).

and how can i fix that?

I would suggest preparing a cost matrix with negative values in the following way:

1. Find the minimal negative value in the original input matrix. In your matrix, it is -0.851823.
2. Add a modulo of this value 0.851823 to all matrix elements.
3. Pass the modified nonnegative matrix into the algorithm.

0         0.7669819  1.84916
1.371147  1.604287   0.904403
1.82337   1.15664    0.540191

The solution will be:

 0    -1    -1
-1    -1     0
-1     0    -1

That means that for the original matrix cost -0.851823 + 0.05258 + 0.304817 = -0.494426 is minimal one.

Please don't hesitate to ask additional questions if it doesn't help.