Wrong answer

[Intel_C_Intel]

In executing this section of code in DVF 6.5A an incorrect answer is calculated for "q.efg(i).pos.e." I set a breakpoint at this line. Before pressing the F11 key to step into this statemnet, the values of the affected variables displayed in the watch window were:

	i =1 
	q,n_of_vectors = 1 
	q.step = 0.500000000 
	q.efg(i).pos.e = 1571.38499309947 
	q.prior_efg(i).pos.e = 1571.38499309947 
	q.prior_efg(i).vel.e = 3.97531397560359 
	a1(i).e = -2.1438381921103193E-003 

After pressing the F11 key to step into the statement, the
value of "q.efg(i).pos.e" changes to 0.993761498957395. When running the same program in DVF 5.0A the value of "q.efg(i).pos.e" is calculated as 1572.37865459843. Using a calculator out to the sixth decimal place the answer is 1572.378888.

             do 230 i=1, q.n_of_vectors 
                q.efg(i).pos.e  
     +                 =q.prior_efg(i).pos.e 
     +                 +(q.step/2.0d0)*q.prior_efg(i).vel.e 
     +                 +(q.step*q.step/8.0d0)*a1(i).e 
                q.efg(i).vel.e  
     +                 =q.prior_efg(i).vel.e 
     +                 +(q.step/2.0d0)*a1(i).e          
                q.efg(i).pos.f  
     +                 =q.prior_efg(i).pos.f 
     +                 +(q.step/2.0d0)*q.prior_efg(i).vel.f 
     +                 +(q.step*q.step/8.0d0)*a1(i).f 
                q.efg(i).vel.f 
     +                 =q.prior_efg(i).vel.f 
     +                 +(q.step/2.0d0)*a1(i).f          
                q.efg(i).pos.g 
     +                 =q.prior_efg(i).pos.g 
     +                 +(q.step/2.0d0)*q.prior_efg(i).vel.g 
     +                 +(q.step*q.step/8.0d0)*a1(i).g 
                q.efg(i).vel.g 
     +                 =q.prior_efg(i).vel.g 
     +                 +(q.step/2.0d0)*a1(i).g          
230          continue 

These are the compiler options I am using in the debug mode.

/check:bounds /check:power /check:overflow /check:underflow
/compile_only /debug:full /nologo /real_size:64 /traceback
/warn:argument_checking /warn:nofileopt /module:"Debug
/" /object:"Debug/" /pdbfile:"Debug
/DF60.PDB" /alignment

Can anyone help me solve this problem? Is there any other information that I could provide to help someone solve the problem? The only thing I know about compilers is how to spell it.

[Steven_L_Intel1]

I suggest sending a copy of your project as a ZIP archive, including everything necessary to reproduce the problem, to us at vf-support@compaq.com

Steve