我正在尝试使用fortran从数据计算值。
program signifikansi
implicit none
integer :: N_energi, N_sudut, i, N
double precision,allocatable :: theta1(:), theta_lab1(:), dsig1(:), dsig_lab1(:), pol1(:), dpolxx1(:), dpolxz1(:), phase1(:), t1(:)
double precision,allocatable :: theta2(:), theta_lab2(:), dsig2(:), dsig_lab2(:), pol2(:), dpolxx2(:), dpolxz2(:), phase2(:), t2(:)
double precision,allocatable :: signif(:)
double precision :: signif_total,signif2
write(*,*)"Masukkan jumlah energi"
read(*,*)N_energi
write(*,*)"Masukkan jumlah sudut pada setiap energi"
read(*,*)N_sudut
N=N_sudut*N_energi
write(*,*)"Total data adalah",N
open(unit=10, file='kminpobs.dat', status="old", action="read")
allocate(theta1(N))
allocate(theta_lab1(N))
allocate(dsig1(N))
allocate(dsig_lab1(N))
allocate(pol1(N))
allocate(dpolxx1(N))
allocate(dpolxz1(N))
allocate(phase1(N))
allocate(t1(N))
do i=1,N
read(10,*) theta1(i), theta_lab1(i), dsig1(i), dsig_lab1(i), pol1(i), dpolxx1(i), dpolxz1(i), phase1(i), t1(i)
end do
close(10)
open(unit=10, file='kminpnoscalar.dat', status="old", action="read")
allocate(theta2(N))
allocate(theta_lab2(N))
allocate(dsig2(N))
allocate(dsig_lab2(N))
allocate(pol2(N))
allocate(dpolxx2(N))
allocate(dpolxz2(N))
allocate(phase2(N))
allocate(t2(N))
do i=1,N
read(10,*) theta2(i), theta_lab2(i), dsig2(i), dsig_lab2(i), pol2(i), dpolxx2(i), dpolxz2(i), phase2(i), t2(i)
end do
close(10)
do i=1,N
signif(i) = (ABS(dsig2(i)-dsig1(i)))/dsig1(i)
end do
signif_total = SUM(signif)
signif2 = signif_total/N
write(*,*)"Hasil signifikansi untuk partikel tersebut adalah",signif2
deallocate(theta1)
deallocate(theta_lab1)
deallocate(dsig1)
deallocate(dsig_lab1)
deallocate(pol1)
deallocate(dpolxx1)
deallocate(dpolxz1)
deallocate(phase1)
deallocate(t1)
deallocate(theta2)
deallocate(theta_lab2)
deallocate(dsig2)
deallocate(dsig_lab2)
deallocate(pol2)
deallocate(dpolxx2)
deallocate(dpolxz2)
deallocate(phase2)
deallocate(t2)
end program signifikansi
这是我的代码，但我得到的只是这样的错误消息
Program received signal SIGSEGV: Segmentation fault - invalid memory reference.
Backtrace for this error:
#0 0x7F0C2BFC2777
#1 0x7F0C2BFC2D7E
#2 0x7F0C2BC1AD3F
#3 0x403034 in MAIN__ at signifikansi1.f90:?
Segmentation fault
输入的N_ergy为39，N_sudut为120。我在输出中得到了N值，但是我的代码无法计算出进一步的结果。
有人可以帮我吗？谢谢。我的猜测是我使用的数组大小太大。
13:26:49 **** Build of configuration Debug for project TestFortran2 ****
make all
Building file: ../TestFortran2.f90
Invoking: GNU Fortran Compiler
gfortran -funderscoring -O0 -g -Wall -c -fmessage-length=0 -o "TestFortran2.o" "../TestFortran2.f90"
../TestFortran2.f90:52:0:
signif(i) = (ABS(dsig2(i)-dsig1(i)))/dsig1(i)
Warning: 'signif.offset' may be used uninitialized in this function [-Wmaybe-uninitialized]
../TestFortran2.f90:55:0:
signif_total = SUM(signif)
Warning: 'signif.offset' may be used uninitialized in this function [-Wmaybe-uninitialized]
../TestFortran2.f90:55:0: Warning: 'signif.dim[0].lbound' may be used uninitialized in this function [-Wmaybe-uninitialized]
../TestFortran2.f90:55:0: Warning: 'signif.dim[0].ubound' may be used uninitialized in this function [-Wmaybe-uninitialized]
Finished building: ../TestFortran2.f90
Building target: TestFortran2
Invoking: GNU Fortran Linker
gfortran -o "TestFortran2" ./TestFortran2.o
Finished building target: TestFortran2
13:26:53 Build Finished. 0 errors, 4 warnings. (took 4s.364ms)
这些是在代码编辑器中显示警告的行，在第51至55行：
do i=1,N
signif(i) = (ABS(dsig2(i)-dsig1(i)))/dsig1(i)
end do
signif_total = SUM(signif)
正如伊恩·布什（Ian Bush）在上面说过的，看来您还没有分配
signif数组。它似乎必须为N大小。因此，我将其添加到代码中，在其他分配的末尾分配，并将其也添加到取消分配的列表中。
然后我清理了构建，并重新构建了所有构建。结果是没有错误或警告。如前所述，如果没有输入文件，我们将无法做更多的事情，但是在您的示例中，由于N的大小只有39 x 120 = 5,000个元素，因此分配问题不大可能出现。您始终可以使用Stat关键字检查分配是否成功：
Allocate(Array(Size),Stat=SuccessCode)
其他几件事。拥有一个良好的IDE是值得的，因为这将使编码更加容易。另外，在编写代码时，缩进代码并不是必需的，但是这样做确实使以后阅读起来容易得多。