Tutorial

  • 04/11/2022
  • Public Content

Building and Running the Coarray Version

The Intel® Fortran Compiler requires that the coarray features are enabled by specifying the
/Qcoarray
option. In Microsoft Visual Studio*, set the project property to
Fortran
Language
Enable Coarrays to For Shared Memory
and then click OK.
Use
Build
Build Solution
to build the application, then
Debug
Start Without Debugging
to run it. On a four-core, eight-thread processor you should see:
Computing pi using 600000000 trials across 8 images Computed value of pi is 3.1416575, Relative Error: .206E-04 Elapsed time is 4.21 seconds
The program can be run with fewer images. Set the project property to
Fortran
Language
Coarray Images to 4
. (The command line option for this is:
/Qcoarray-num-images:4
.) Build and run the program. You should see:
Computing pi using 600000000 trials across 4 images Computed value of pi is 3.1415352, Relative Error: .183E-04 Elapsed time is 5.53 seconds
The time goes up because the work is now spread across four physical cores.
You can control the number of images through the environment variable:
FOR_COARRAY_NUM_IMAGES
.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.