fortran90

问题 I am a beginner of fortran90. Now I am trying to learn fortran code and I am not clear with the description of the write format write ( *, '(2x,i4,2x,g14.6,2x,14x,2x,g14.6)' ) 0, unew_norm, error Can anybody explain to me what does '(2x,i4,2x,g14.6,2x,14x,2x,g14.6)' stuff mean. It would be very nice to teach me the dummy things. Best 回答1: From this source: nX means that n spaces are added to the line; iw means that an integer (hence the i ) is printed in a field w spaces wide; gw.p is a

问题 I am looking for reading a file, like: NE 32 0 IBZINT 2 NKTAB 936 XC-POT VWN ITER 29 MIX 2.00000000000000E-01 TOL 1.00000000000000E-05 I was thinking it is index intrinsic that I am looking for, and was writing a code accordingly: EDIT The code is updated, Implicit None integer ::i,pos character(50) :: name character(len=16),dimension(100)::key,val key(1)="NE" open(12,file="FeRh/FeRh.pot_new",status="old") do i=1,100 read(12,*)name if (name(1:2)==key(1))then write(*,*)"find NE" write(*,*)name

问题 I have an optimization solver in Fortran 90. So, if I want to change the objective function I have to modified the main file and write the objective function in this way: subroutine fobj(n,x,f) implicit none integer :: n real(8) :: f real(8) :: x(n) intent(in ) :: n,x intent(out) :: f !OBJECTIVE FUNCTION f = x(1)**2-x(2)+2*x(3) end subroutine fobj I have a big objective function, so I want to call this line "f = x(1)**2-x(2)+2*x(3)" from an external file or at least the subrutine. Is that

问题 I am creating graph using the adjacency list method. Each node is represented as a node which points to other nodes connected to it. The following is my code program main use graphs implicit none type(node),pointer :: start type(node), dimension(:), pointer :: grp integer :: n, ios=0, a,b, i open(1, file='test6.txt', status='OLD', action='READ') read(1,*,iostat=ios) n allocate(start) allocate(grp(n)) do, i=1,n grp(i)%val=i enddo do while(ios==0) read(1,*, iostat=ios)a,b if(ios.NE.0)then exit

问题 I need to work on Fortran90 code on my Macbook Pro, which was written on Microsoft Developer Tools years ago. As a free option, I have installed gfortran on my Macbook to be able to compile it. The original code includes & continuation character for the long lines but I am not able to use it. Without & character, everything works fine. What might be the problem? Do I need to activate something to be able to use & character? For example, I think something like this should work: x = 1 y = 2 z =

问题 I am trying to convert an integer to character in my program in Fortran 90. Here is my code: Write(Array(i,j),'(I5)') Myarray(i,j) Array is an integer array and Myarray is a character array, and '(I5)' , I don't know what it is, just worked for me before! Error is: "Unit has neither been opened not preconnected" and sometimes "Format/data mismatch"! 回答1: Alexander Vogt explains the meaning of the (I5) part. That answer also points out some other issues and fixes the main problem. It doesn't

问题 I want to do some arithmetic operation to an array of real number and later I have to read it as an input for character variable. I used read statement still I get the error as UNIT SPECIFICATION MUST BE AN INTEGER OR CHARACTER VARIABLE. I also verified the format descriptor. Here is my piece of code real::la(10), sl integer::i character(len=5)::lat character(len=7)::station sl=11.25 do i=1,10 la = sl+ (i*0.25) read(la(i),'(F5.2)')lat station= lat//'xx' end do 回答1: When you have read(la(i),'

问题 I try to implement a code that read in a number n, creates a vector to store n double precision numbers, read this number, call a subroutine printminmax() to find min and max. My code work perfect for normal numbers (integer,real etc) but when i have scientific notation (0.3412E+01) stack.Why? I thought with * read all the formats. Thanks implicit none integer, dimension(:), allocatable :: x integer :: n open (unit=77, file='input2.dat', action='read', status='old') read(77,*), n allocate(x(n

问题 I have the following problem. I have a file that I must: divide in cells to create an NxN grid; counts the particles in each cell; write the resulting numbers in a particular way. The problem is the third point: I must write an NxN array each numbers represent the total numbers of particles in each cell, but I don't know how to write the file in an NxN array. program eccen implicit none integer, parameter:: grid=200 integer::i,j,k,n,m real*8,allocatable::f(:,:) real*8::xx(grid),yy(grid),mval

问题 This question already has an answer here : Closed 7 years ago . Possible Duplicate: postfix 'd+0' in Fortran real literal expressions I have this code line in Fortran 90: OVERN2 = 1.d+0/DBLE(FLOAT(NMODE2)) NMODE2 is an integer, OVERN2 is a REAL*8 . Can you please explain to me what this line does? I don't understand the .d+0/ part? if you can also translate that to C or any other easier language. 回答1: 1.d+0 is just a double precision literal in scientific notation, i.e. 1.0e0 or just 1.0. In