I'm getting a "Segmentation fault: 11" when running at line 72:(adsbygoogle = window.adsbygoogle || []).push({});

However, the line above it:Code (Text):IF (h_temp == blayer) THENruns just fine. Needless to say, I'm clueless. Here's my entire code.Code (Text):PRINT *,h_temp==blayer

Any clue what's happening here?Code (Text):PROGRAM bunkers

IMPLICIT NONE

REAL, DIMENSION(5) :: ulist,vlist,hlist

REAL, DIMENSION(2) :: wind

INTEGER :: numvars

ulist = (/ 1,2,3,4,5 /)

vlist = (/ 4,5,6,6,7 /)

hlist = (/ 100,200,300,400,500 /)

numvars = SIZE(ulist)

CALL meanwind(ulist,vlist,hlist,numvars,150.0,450.0,wind)

PRINT *,'The mean wind is', wind

STOP

END PROGRAM bunkers

SUBROUTINE lininterp(ulist,vlist,hlist,numvars,targetlvl,u,v)

IMPLICIT NONE

!Dummy argument declarations

INTEGER, INTENT(IN) :: numvars

REAL, DIMENSION(numvars), INTENT(IN) :: ulist,vlist,hlist

REAL, INTENT(IN) :: targetlvl

REAL, INTENT(OUT) :: u,v

!Local variable declaration

REAL :: spacing, currenth, nexth

INTEGER :: i

spacing = hlist(2) - hlist(1)

DO i=1,SIZE(hlist)

currenth = hlist(i)

nexth = hlist(i+1)

IF (targetlvl>currenth .AND. targetlvl<nexth) THEN

u=(ulist(i+1)-ulist(i))/spacing*(targetlvl-hlist(i))+ulist(i)

v=(vlist(i+1)-vlist(i))/spacing*(targetlvl-hlist(i))+vlist(i)

END IF

END DO

RETURN

END SUBROUTINE lininterp

SUBROUTINE meanwind(ulist,vlist,hlist,numvars,blayer,tlayer,wind)

IMPLICIT NONE

!Dummy argument declarations

INTEGER, INTENT(IN) :: numvars

REAL, INTENT(IN) :: blayer,tlayer

REAL, DIMENSION(numvars), INTENT(IN) :: ulist,vlist,hlist

REAL, DIMENSION(2), INTENT(OUT) :: wind

!Local variable declaration

REAL :: umodmean, vmodmean, u, v,angle, headnewx_1, headnewx_2, h_temp,u_temp,v_temp

INTEGER :: i,j,vmod

REAL, ALLOCATABLE, DIMENSION(:) :: tailvect,headvect

REAL, DIMENSION(2,1) :: a, headnewx, meanwindmat

REAL, DIMENSION(2) :: vector,modheadvect,vect,modmean

REAL, DIMENSION (2,2) :: rotation,counter

!Find head and tail wind vectors

DO i=1,numvars

h_temp = hlist(i)

u_temp = ulist(i)

v_temp = vlist(i)

PRINT *,h_temp==blayer

IF (h_temp == blayer) THEN

ALLOCATE(tailvect(2))

tailvect = (/ u_temp,v_temp /)

ELSE IF (h_temp == tlayer) THEN

ALLOCATE(headvect(2))

headvect = (/ u_temp, v_temp /)

ELSE IF (h_temp >= tlayer) THEN

EXIT

ELSE

EXIT

END IF

END DO

IF (.not. allocated(tailvect)) THEN

CALL lininterp(ulist,vlist,hlist,numvars,blayer,u,v)

tailvect = (/ u,v /)

END IF

IF (.not. allocated(headvect)) THEN

CALL lininterp(ulist,vlist,hlist,numvars,tlayer,u,v)

headvect = (/ u,v /)

END IF

!Move coord sys so tail vect is origin

modheadvect = (/ headvect(1)-tailvect(1),headvect(2)-tailvect(2) /)

angle = acos(modheadvect(1) / sqrt(modheadvect(1)**2.0 + modheadvect(2)**2.0))

IF (modheadvect(2) .lt. 0) THEN

angle = -1*angle

END IF

rotation = RESHAPE((/ cos(angle),sin(angle),-1*sin(angle),cos(angle) /),(/2,2 /))

counter = RESHAPE( (/cos(angle),-1*sin(angle),sin(angle),cos(angle) /),(/2,2/))

!Rotate hodograph so x-axis along mean shear vector

vmod = 0

j = 0

DO i = 1,SIZE(hlist)

IF (hlist(i) .ge. blayer .and. hlist(i) .le. tlayer) THEN

vect = (/ ulist(i) - tailvect(1),vlist(i)-tailvect(2) /)

a = RESHAPE((/ rotation(1,1)*vect(1)+rotation(2,1)*vect(1),rotation(1,2)*vect(2),rotation(2,2)*vect(2) /),(/2,1/))

vmod = vmod + a(2,1)

j = j + 1

ELSE IF (hlist(i) .gt. tlayer) THEN

EXIT

ELSE

EXIT

END IF

END DO

!Rotate head vector to make it new x-axis

headnewx_1 = rotation(1,1)*modheadvect(1)+rotation(2,1)*modheadvect(1)

headnewx_2 = rotation(1,2)*modheadvect(2)+rotation(2,2)*modheadvect(2)

headnewx = RESHAPE((/headnewx_1,headnewx_2/),(/2,1/))

!WIND MEASUREMENTS MUST BE EVENLY HEIGHT-DISTRIBUTED IN THE VERTICAL FOR THESE TO WORK

!Mean u wind is half of diff b/w bottom and top u

umodmean = headnewx(1,1) / 2.0

!Mean v wind is average of v obs in coord sys

vmodmean = vmod/j

!Rotate coord system back

meanwindmat = RESHAPE((/counter(1,1)* umodmean,counter(2,1)*vmodmean/),(/2,1/))

!Add mean wind to tail vector for true mean wind vector

wind = (/meanwindmat(1,1)+tailvect(1),meanwindmat(2,1)+tailvect(2)/)

RETURN

END SUBROUTINE meanwind

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# Fortran Segmentation Fault

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