Zero initialization is assumed!

[xecej4]

The driver programs do not assign zero initial values to the variable arrays x, Fvec and Fjac. Only the nonzero initial values are programmed. As a result, if the Fortran compiler in use does not provide a switch to do zero-initialization, or the user does not use the switch, the results will most probably be completely wrong.

Correcting this deficiency should also take care of issue #5.

[jacobwilliams]

Yep, these tests have not been modernized. Probably there are lot of things to fix. thanks for reporting this (and the others)

[xecej4]

The fixes are quite simple. For the driver test_lmder.f90, here are the fixes.

Add the following as the first executable statement in subroutine SSQJAC:
Fjac(1:m,1:n) = 0.0d0
Similarly, add as the first executable statement in INITPT:
X(1:n) = 0.0d0
and as the first executable statement in SSQFCN:
Fvec(1:m) = 0.d0

Similar changes apply to the other drivers. For test_lmstr.f90, add ",Save" to the declaration of TEMP in subroutine FCN.

[jacobwilliams]

I'm not quite seeing why the temp needs a save attribute.

[jacobwilliams]

oh wait...I just saw #7.

[awvwgk]

In the C test I solved this by introducing more cases and actually calculate the Jacobian row by row rather than once and rely on save / static to retrieve the previously calculated values.