These two intrinsics report different types of time. system_clock reports “wall time” or elapsed time. cpu_time reports time used by the CPU. On a multi-tasking machine these could be very different, e.g., if your process shared the CPU equally with three other processes and therefore received 25% of the CPU and used 10 cpu seconds, … Read more
Use (gdb) print *((real *)A+m)@n where A is the array, m is the shift in the position (no need to write +m in the case m=0) and n is the number of elements that you want to print. If you’re working with double precision reals then replace real by real_8. Also, for integers replace real … Read more
One method: read the line into a string, using a string that is at least as long as the longest expected line. Then you go about parsing the string. E.g., if the numbers are always split by spaces, use that to figure out the substring boundaries. Then you can use “internal reads” to read from … Read more
When compiling with ifort before version 17.0.1, the default behaviour is for the compiler not to use the Fortran rules for automatic allocation on intrinsic assignment. You will need to use an option like -assume realloc-lhs.
This should work too: PRINT *, ‘I am a new learner of & &fortran’ That is, character literals can be continued across line breaks but each continuation line must have an ampersand in the first non-blank position.
They are equivalent. There is no difference in their usage. You can employ this to print one of the quotation characters: print *, “‘” print *, ‘”‘ prints first ‘ and then “. Note: You can also use two quote characters in a row to print one: print *, “””” print *, ”” prints first … Read more
Yeah, pointer arrays are funny in Fortran. The problem is that this: TYPE(domain),DIMENSION(:),POINTER :: dom does not define an array of pointers, as you might think, but a pointer to an array. There’s a number of cool things you can do with these things in Fortran – pointing to slices of large arrays, even with … Read more
Fortran doesn’t automatically skip comments lines in input files. You can do this easily enough by first reading the line into a string, checking the first character for your comment symbol or search the string for that symbol, then if the line is not a comment, doing an “internal read” of the string to obtain … Read more
With RESULT(FluxArray), fluxArray is the name of the result variable. As such, your attempt to declare the characteristics in the result clause are mis-placed. Instead, the result variable should be specified within the function body: function Flux(W1,W2) result(fluxArray) double precision, dimension(3), intent(in)::W1, W2 double precision, dimension(3) :: fluxArray ! Note, no intent for result. end … Read more