Create array with elements of different type in Fortran

Question

Exactly the same questions as Create an array with elements of different types, except how to do this in Fortran?

Say I want an array with the first dimension an integer type, the second real and the third character (string) type. Is it possible to create a "struct" in Fortran too?

Thanks.

Community · Accepted Answer · 2017-05-23 11:47:14Z

9

Here is an example program of a derived type use:

TYPE mytype
  INTEGER,DIMENSION(3)   :: ints
  REAL,DIMENSION(5)      :: floats
  CHARACTER,DIMENSION(3) :: chars
ENDTYPE mytype

TYPE(mytype) :: a

a%ints=[1,2,3]
a%floats=[1,2,3,4,5]
a%chars=['a','b','c']

WRITE(*,*)a

END

The output is:

        1            2            3    1.000000        2.000000     
3.000000        4.000000        5.000000     abc

EDIT: As per suggestion by Jonathan Dursi:

In order to have an array where each element has a int, float and char element, you would do something like this:

TYPE mytype
  INTEGER   :: ints
  REAL      :: floats
  CHARACTER :: chars
ENDTYPE mytype

TYPE(mytype),DIMENSION(:),ALLOCATABLE :: a

ALLOCATE(a(10))

You would then reference your elements as, e.g. a(i)%ints, a(i)%floats, a(i)%chars. Related answer is given in Allocate dynamic array with interdependent dimensions.

edited May 23, 2017 at 11:47

CommunityBot

11 silver badge

answered Dec 19, 2011 at 5:26

milancurcic

6,2413 gold badges39 silver badges49 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Jonathan Dursi Over a year ago

Just to add; IRO-bot's answer correctly gives you a derived type which contains arrays of ints, floats, and chars. If you wanted an array of (type containing int + float + char), you'd define your type as above but without DIMENSIONS on the types - eg, a single int, float, and char - and then define eg. TYPE(mytype), DIMENSION(10) :: a or TYPE(mytype), ALLOCATABLE, DIMENSION(:), :: a and later allocate(a(10)).

milancurcic Over a year ago

@JonathanDursi Thanks for the suggestion - I added this to the answer.

Samuel Tan Over a year ago

Thanks very much, guys. This is very helpful. So using derived types I can construct from the mainstream/default types my own type, the shape/dimension of which I can state in the definition or, even better, allocate it later based on how the program runs. Sweet.

Collectives™ on Stack Overflow

Create array with elements of different type in Fortran

1 Answer 1

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related