修正一处bug，VTK_fortran.f90 格式化输出格式不规范，无法在gfortran环境中编译，现已改为标准格式

tem3dfdtd/module/VTK_fortran.f90

@@ -1,4 +1,4 @@
-!Copyright (c) 2022 by LEEE under guide of Huaifeng Sun(sunhuaifeng@gmail.com)
+!Copyright (c) 2022 by LEEE under guide of Huaifeng Sun(sunhuaifeng@email.sdu.edu.cn)
 !written by Qi Zhao(zhaoqi_326326@163.com)
 
 ! --------------------------------Subroutine part---------------------------------------------!
@@ -204,7 +204,7 @@ Module VTK_Fortran
                     do i=1,NXB
                         
                         temp = temp + 1
-                        write(unit, fmt='(3f)', iostat=error) Coord_x(i), Coord_y(j), Coord_z(k)
+                        write(unit, fmt='(3F25.16)', iostat=error) Coord_x(i), Coord_y(j), Coord_z(k)
                         
                     end do
                 end do
@@ -250,7 +250,7 @@ Module VTK_Fortran
                 do j=1, NY
                     do i=1,NX
                         temp = temp + 1
-                        write(unit, fmt='(9i)', iostat=error)nums,&
+                        write(unit, fmt='(9I12)', iostat=error)nums,&
                             ((i  ) + (j-1)*NXB + (k-1)*NXB*NYB) -1,  &
                             ((i+1) + (j-1)*NXB + (k-1)*NXB*NYB) -1,  &
                             ((i  ) + (j  )*NXB + (k-1)*NXB*NYB) -1,  &
@@ -266,7 +266,7 @@ Module VTK_Fortran
             write(unit=unit,fmt='(A,I0,A,I0)', iostat=error) "CELL_TYPES ", cells
             
             do i=1, temp
-                write(unit, fmt='(i)', iostat=error)num_cell_types
+                write(unit, fmt='(I12)', iostat=error)num_cell_types
             end do
             write(unit=unit,fmt='(2A,I0)', iostat=error) Value_site_cell," ", cells
 
@@ -311,7 +311,7 @@ Module VTK_Fortran
                 do j=1, NY
                     do i=1,NX
                         temp = temp + 1
-                        write(unit, fmt='(f)', iostat=error)values(i,j,k)
+                        write(unit, fmt='(F25.16)', iostat=error)values(i,j,k)
                     end do
                 end do
             end do