Intel® Fortran Composer XE

Getting Nan


I'm getting NaN as answer for expressions like below

MN1=WTAP/( SQRT(GC*GAMA1/R1)*(1.0+(GAMA1-1.0)/2.0*
     &    MN1**2.0)**((GAMA1+1.0)/(2.0*(1.0-GAMA1))) )

All are real variables and they have real values.

When I simplify the expression , it gives the correct answer. But then I am getting Nan as answer for a another expression. Then I have to simplify it also. 

Please help me.

Thank you. 

Intel visual Fortran Compiler 


How to control the initial item in VS

When I open a project in Visual Studio, what controls the "initial item"? I have one project which, most of the time but not always, the working item display tries to open a static library item that is a part of the project (and shows as such in the Solution Explorer window) Of course this item contains only object code, so the working window shows only binary stuff in Hex. This has become quite annoying. If I switch to display a source code item and then close VS, the next time I open the project it will start with that item--as I would expect--but this behavior does not stick.

Invoking constructor of abstract base class in Fortran

I originally posted this question on Stackoverflow (, but perhaps the Intel community har more knowledge on this topic?

Consider one of the classic OOP examples (see source code at the end of the post):

  • Abstract base class Shape
  • Class Rectangle extending Shape

I have two questions:

Use of signaling nan

I have been liberally using non-signalling nans as a debug aid. I can use these anywhere an initialization expression is allowed. But having no signalling limits the usefulness of this method.

I tried to make use of the new option Qinit:snan but that is only applicable to local scalars which are a small subset of the cases I need.

I create a parameter for my initialization like this:

real(DP), parameter :: aNaN = 0.0D0 / 0.0D0.

and declare arrays within derived types like this:

Missing warning for dummy argument with an explicit INTENT(OUT) being used before it is defined.

Consider the following simple code snippet.  Intel Fortran does give a warning if the procedure does not give a value to a dummy argument with an explicit INTENT(OUT) attribute.  However a warning if such a variable is used before being defined is missing; it'll be very helpful if the compiler can warn for this situation as well.

Can't get Intel Fortran compiler after installation!!


I downloaded the trial version of Intel Parallel Studio XE 2015 Cluster version. It's the update 4 version. And I tried to install it in my computer. However, after I installed it, it only shows some documentations. I couldn't find the tools folder. So I can't use Intel fortran compiler. I wonder what I can do about it. Is this because I am using the trial version?

Thank you so much.  

Need compiler switch to set variables to 4-bytes in 64-bit build

I have some mixed C/Fortran code in VS2010.  I get different results from the 32-bit and 64-bit builds of the code.  To see if it is a precision problem, I would like to compile the 64-bit  build with a switch that forces the real and integer variables to be single precision (4-bytes).  Are there switches for the C and Fortran compilers to do this?  Please let me know.  Thank you.

fpconstant issue

I always use /fpconstant to save having to append d0 to all my constants.  As far I was aware this has always worked.  But now it works for one constant but not another.

      program ww
      implicit none
      real*8 :: KTOFShift      = -459.67
      real*8 :: KTOFFact       = 1.8
      write(6,*) KTOFShift
      write(6,*) KTOFFact


ifort  ww.f90

ifort  ww.f90 /fpconstant

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