# Error: Rank mismatch in argument ‘cars’ at (1) (scalar and rank-1) **URL:** \ **Category:** Help\ **Created:** [March 28, 2022, 6:16pm UTC](https://fortran-lang.discourse.group/t/error-rank-mismatch-in-argument-cars-at-1-scalar-and-rank-1/3062 "2022-03-28T18:16:23Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![giraffe](https://avatars.discourse-cdn.com/v4/letter/g/f1d935/32.png) [@giraffe](https://fortran-lang.discourse.group/u/giraffe)\ **Post date:** [March 28, 2022, 6:16pm UTC](https://fortran-lang.discourse.group/t/error-rank-mismatch-in-argument-cars-at-1-scalar-and-rank-1/3062/1 "2022-03-28T18:16:23Z")
With these compiler options, how do I prevent this error and maintain the logic in the program? `-g -Wall -Werror -fmax-errors=1 -fcheck=all` ```auto SUBROUTINE TESTING (cars) CHARACTER cars*(*) print *,"CARS=", cars(1),cars(2),cars(3) end Program TEST Character test1 * 10 Character test2 * 30 COMMON /ABC/test1(10) COMMON /DEF/test2(30) test1(1)= 'A' test1(2)= 'B' test1(3)= 'C' CALL TESTING (test1) test2(1)= 'X' test2(2)= 'Y' test2(3)= 'Z' CALL TESTING (test2) End Program TEST ``` ```auto Error Message: 13 | CALL TESTING (test1) | 1 Error: Rank mismatch in argument ‘cars’ at (1) (scalar and rank-1) [-Werror=argument-mismatch] f951: all warnings being treated as errors ``` ---
**Author:** ![alozada](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/alozada/32/298_2.png) [@alozada](https://fortran-lang.discourse.group/u/alozada)\ **Post date:** [March 28, 2022, 6:49pm UTC](https://fortran-lang.discourse.group/t/error-rank-mismatch-in-argument-cars-at-1-scalar-and-rank-1/3062/2 "2022-03-28T18:49:00Z")
With some changes seems to work, 🙂 ```auto module testing_mod implicit none character(len=10) :: test1(10) character(len=30) :: test2(30) contains subroutine testing_sub (cars) character(*) :: cars(:) print *,"CARS=", cars(1),cars(2),cars(3) end subroutine testing_sub end module testing_mod program test use testing_mod test1(1)= "A" test1(2)= "B" test1(3)= "C" call testing_sub(test1) test2(1)= "X" test2(2)= "Y" test2(3)= "Z" call testing_sub(test2) end program test `` gfortran -g -Wall -Werror -fmax-errors=1 -fcheck=all rank.f90 -o rank ./rank CARS=A B C CARS=X Y Z ``` ---
**Author:** ![alozada](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/alozada/32/298_2.png) [@alozada](https://fortran-lang.discourse.group/u/alozada)\ **Post date:** [March 28, 2022, 7:24pm UTC](https://fortran-lang.discourse.group/t/error-rank-mismatch-in-argument-cars-at-1-scalar-and-rank-1/3062/4 "2022-03-28T19:24:01Z")
The `if` clause requires a scalar logical expression you could use something like: ```auto do i = 1, n if (cars(i)(1:1) == '<' ) print*, "works" end do ``` ---
**Author:** ![msz59](https://avatars.discourse-cdn.com/v4/letter/m/3d9bf3/32.png) [@msz59](https://fortran-lang.discourse.group/u/msz59)\ **Post date:** [March 28, 2022, 8:32pm UTC](https://fortran-lang.discourse.group/t/error-rank-mismatch-in-argument-cars-at-1-scalar-and-rank-1/3062/5 "2022-03-28T20:32:31Z")
Maybe it is worth explaining the problem with original source, apparently Fortran 77 standard, as there are several errors in it. 1. `CHARACTER cars*(*)` tells the compiler that the dummy argument `cars` will be an object of type _assumed length character scalar_, not an array! It is F77 way of modern `CHARACTER(LEN=*)`. Furthermore, the nature of this object is deduced by the compiler only when it finds it in context, here the context is `print *,"CARS=",cars(1)...`. As `cars` is a scalar, not an array, `cars(1)` is interpreted as a function call, thus making the `cars` a dummy procedure! 2. In the main program, `test1` and `test2` are defined as arrays (1-dimensional, a.k.a. rank-1) of character elements having the length of 10 and 30, respectively. This is why you get `Rank mismatch.. (scalar and rank-1)` at `CALL TESTING()` statement. So, to keep the old format, you’d have to change the dummy declaration to `CHARACTER*(*) cars(*)` to make it an _array of assumed length character elements_ To get convinced about the point 1 above regarding the _dummy procedure_, change (in the original code!) the `test1` and `test2` in `CALL TESTING()` to any scalar character value, say `"abc"` and `"def"` and compile. You’ll get something like: `Error: Expected a procedure for argument 'cars'` Surely @alozada’s solution is much better, converted to modern Fortran. ---
**Author:** ![ivanpribec](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/ivanpribec/32/3290_2.png) [@ivanpribec](https://fortran-lang.discourse.group/u/ivanpribec)\ **Post date:** [March 29, 2022, 6:11am UTC](https://fortran-lang.discourse.group/t/error-rank-mismatch-in-argument-cars-at-1-scalar-and-rank-1/3062/6 "2022-03-29T06:11:43Z")
> [@msz59](#): > > Surely @alozada’s solution is much better, converted to modern Fortran. An implicit none would be nice. Goes to show how easy it can be to forget. ---
**Author:** ![alozada](https://yyz2.discourse-cdn.com/free1/user_avatar/fortran-lang.discourse.group/alozada/32/298_2.png) [@alozada](https://fortran-lang.discourse.group/u/alozada)\ **Post date:** [March 29, 2022, 7:17am UTC](https://fortran-lang.discourse.group/t/error-rank-mismatch-in-argument-cars-at-1-scalar-and-rank-1/3062/7 "2022-03-29T07:17:20Z")
> [@ivanpribec](#): > > An implicit none would be nice. of course, 😳 . `implicit none` ---
**Author:** ![msz59](https://avatars.discourse-cdn.com/v4/letter/m/3d9bf3/32.png) [@msz59](https://fortran-lang.discourse.group/u/msz59)\ **Post date:** [March 29, 2022, 3:06pm UTC](https://fortran-lang.discourse.group/t/error-rank-mismatch-in-argument-cars-at-1-scalar-and-rank-1/3062/9 "2022-03-29T15:06:45Z")
> [@giraffe](#): > > How do you get ‘B’, ‘C’, ‘Y’, and ‘Z’ to be output? By reading and applying my earlier hint? > [@msz59](#): > > So, to keep the old format, you’d have to change the dummy declaration to > `CHARACTER*(*) cars(*)` As it is now, without the magical `*(*)` , `cars` dummy argument is an array of len=1 character elements. And you are sending arrays of len=10 or len=30 elements