Hi, I have a large amount of arrays of different dimensions. However, I name them with a sequential order, say var1, var2, and so on. In order to read them, I would be interested in looping over them in something like: do i=1,n read(1,*) var<i> enddo Of course, since the arrays are of different dimensions, I cannot simply add a ...
I've written a function which calculates the eigenvalues of a 2*2 matrix. It takes a 2*2 matrix as an argument and returns 2 eigenvalues via a 2-element array. I have declared the function in the program unit like this: real, dimension(2), external :: eigenvalues But it won't compile, it comes up with this error: Error: EXTERNAL attr...
An usual read statement in Fortran interrupts the execution of the program until the RETURN key was pressed. I am looking for a statement that reads any pressed key without waiting for the RETURN key. The program should not stop even if no key was pressed. Thank you for your answer. Edit: Here is some source code that should clarify the...
I have an input file and the first line contains the following decimal. 0.5053102074297753 I have a Fortran 90 program which reads the file and outputs the value. read(*,*) answer write(*,"(F20.16)") answer This is the output: 0.5053101778030396 Apparently, what is stored is not the same as what is read. The question is, Why? ...
It is my understanding that you can return an array from a function in Fortran, but for some reason my code is only returning the first value in the array I am asking it to return. This is the function: function polynomialMult(npts,x,y) integer npts double precision x(npts), results(npts + 1), y(npts,npts) polynomialMult = ...
Getting this error while trying to compile a copied code from a fortran 77 program. code: 900 FORMAT(1H0,2X,'ABSOLUTE GRID LIMITS FOR DATA RETENTION FOR RADAR',I3,' XMIN-XMAX ',2F8.3,' YMIN-YMAX ',2F8.3,' ZMAX ',F8.3, /3X,'WITH AZIMUTH LIMITS OF',2F8.2, 3X,'AND RANGE LIMITS OF',2F10.3,/) compiler error: messy21.f90:529.132: N FOR R...
in fortran, you can pass a function/subroutine A as an argument to another function/subroutine B, but can you store A for later retrieval and use? for example, this is allowed in C int foo(float, char, char) { /*whatever*/}; int (*pointerToFunction)(float, char, char); pointerToFunction = foo; In Fortran you can pass a subroutine as...
I'm having trouble trying to compile a simple fortran program which uses a module in the same directory. I have 2 files: test1.f90 which contains the program and modtest.f90 which contains the module. This is test1.f90: program test use modtest implicit none print*,a end program test This is modtest.f90: module modtest impli...
I am somewhat puzzled by the following program module test implicit none type TestType integer :: i end type contains subroutine foo(test) type (TestType), intent(out) :: test test%i = 5 end subroutine subroutine bar(test) type (TestType), intent(out) :: test test%i = 6 end subrout...
I have a user-defined type vector. In another type, I have an allocatable array of vectors. I want to have a pointer to a single vector from this allocatable array. So I thought I would do this: type(vector),allocatable,target::my_vectors(:) and type(vector),pointer::pointed_vec But when I compile, the compiler complains that: Thi...
my program is as follows: module x use mpi !x includes mpi module implicit none ... contains subroutine do_something_with_mpicommworld !use mpi !uncommenting this makes a difference (****) call MPI_...(MPI_COMM_WORLD,...,ierr) end subroutine ... end module x program main use mpi use x MPI...
I always assumed that fortran passed entities "by reference" to a dummy argument. Then I got this answer (the actual argument of the answer was related, but not on this) The standard never specifies that and, indeed goes quite a lot out of its way to avoid such specification. Although yours is a common misconception, it was n...
what is the difference between these two codes type Foo real, allocatable :: bar(:) end type and type Foo real, pointer :: bar(:) end type in particular when it comes to the following code: type(Foo) :: myfoo allocate(myfoo%bar(10)) ...