Weird to the power error

[berrydenhartog]

I'm doing matlab calculation with visual fortran 90. Now ihave a strange error.

When i use the ** symbol my mex dll crashes. without the ** it works great.

also the5 ** 2 works great (propably becouse optimalization makes it a5 * 5) but5 ** 0.25 dosn't work.

My testing code

REAL*8 FUNCTION T4_p(p)

IMPLICIT NONE

REAL*8 beta

REAL*8 p

beta = p ** 0.25 also tryed beta = p ** 0.25D0

T4_p = beta

RETURN

End

Do i need to add a lib to my linker? dos anyone know what i am doing wrong.

[jimdempseyatthecove]

Berry,

Put a breakpoint on the beta = line and examine what p references.

Also, look one level up the call stack and see where and whatthe function (T4_P) is pointing at.

Check for mis-typed variabes as well as undefined variables and if p references NaN, Inf etc...

Does this function have/use interfaces?

Jim Dempsey

[Steven_L_Intel1]

How does it "crash"? What is the error message? If this is being built into a DLL, you need libmmd.lib

[TimP]

sqrt(sqrt(p)) ought to be more efficient than p**.25.

[berrydenhartog]

Thanks allot Steve, when i added that lib everything works great. i was also trying stuff like this: (maybe it will help someone else)

REAL*8 FUNCTION GetPower(base,exponent)
IMPLICIT NONE
REAL*8 exponent,base

if(exponent .EQ. 0.D0) then
GetPower = 1.D0
RETURN
end if
If(base .EQ. 0.D0) then
GetPower = 0.D0
RETURN
end if
if(exponent .EQ. 2.D0) then
GetPower = base * base
RETURN
end if

GetPower = DEXP(exponent * DLOG(base))
RETURN
End

But also crashed my mex dll file.

Thx for that tip tim18, I didn't tought about that on.

the error was

??? Invalid MEX-file 'Path': The specified module could not be found.

.