subroutine tabva2

[VzHache]

Hello,

I am trying to use the subroutine forcem that calls tabva2.
I'm facing with strange behaviour I do not understand.
A table that aims to increase linearly the load is included in the bulk file:
table table1
1 1 0 0 2
1 2 1 0 0 1 0 0 2 0 0 2
0.000000000000000+0 0.000000000000000+0
1.000000000000000+0 1.000000000000000+0
Then, the forcem subroutine is called for the application of pressure:
dist loads

1 1 0 0 0 0apply3
1.000000000000000+1
1
0 1
13
apply3_edges


My calculation is done in 4 increments: 0.25, 0.5, 0.75, 1.
I would like checking thevalue send back by tabva2 subroutine and introduced the following lines in the forcem:
write(6,*) "Check table"
do x=0,1.,0.5
call tabva2(x,P1,1,0,0)
write(6,*) x,P1
enddo

Here is what I got:
increment 0:
Check table
0.000000000000000E+000 0.000000000000000E+000
0.500000000000000 0.000000000000000E+000
1.00000000000000 0.000000000000000E+000

increment 0.25:
Check table
0.000000000000000E+000 0.000000000000000E+000
0.500000000000000 0.125000000000000
1.00000000000000 0.250000000000000

increment 0.5:
Check table
0.000000000000000E+000 0.000000000000000E+000
0.500000000000000 0.250000000000000
1.00000000000000 0.500000000000000

increment 0.75:
Check table
0.000000000000000E+000 0.000000000000000E+000
0.500000000000000 0.375000000000000
1.00000000000000 0.750000000000000

increment 1.:
Check table
0.000000000000000E+000 0.000000000000000E+000
0.500000000000000 0.500000000000000
1.00000000000000 1.00000000000000

With that results, the load factors considered in forcem (and coming from table 1) are:
0.25=>0.0625
0.5=>0.25
0.75=>0.5625
1=>1.
and not
0.25=>0.25
0.5=>0.5
0.75=>0.75
1=>1.

Can anybody explain me why the values coming from tabva2 differ from increment to another and do not match with the table?

Many thanks in advance for your support.

Regards,
VzHache