running a f90 code in f77 compiler

[vissu219]

heys..can anyone tell me..how could i run f90 codes in an f77 compiler..wht changes in the code do i need to make to do that?

[zeitghost]

Have you tried running it through the compiler to see what error messages it generates?

[vissu219]

no.. but i figured out that.. i have to move each line of code such that it starts at the 7th column to run in f77 compiler..i dont know wht other changes to be made

[Dr Transport]

It will be a lot of work, other than the shifting of all of the lines of code to appropriate position, f90 intrinsic functions will have to be rewritten in f77 syntax, the first that comes to mind is MATMUL(A,B) which is a matrix multiplication routine. It will become a set of nested DO-loops, unless you write a function, then you only have to do it once, but there are others to look for and the compiler will find them for you.

[zeitghost]

Is the f90 source in freeform format? (i.e. not tabbed out to column 7).

Does the f77 compiler support freeform?

How much code is there? 1k lines, 10k, 100k? or more?