subtypes or composite types. commonly applies to sql or polymorphism/reflection in fortran or C#
Questions tagged [derived-types]
167 questions
106
votes
3 answers
How does deriving work in Haskell?
Algebraic Data Types (ADTs) in Haskell can automatically become instances of some typeclasses (like Show, Eq) by deriving from them.
data Maybe a = Nothing | Just a
deriving (Eq, Ord)
My question is, how does this deriving work, i.e. how does…
Abhinav Sarkar
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17
votes
1 answer
SignalR 2.0 change Json Serializer to support derived type objects
Please note that I'm explicitly referencing SignalR 2.0 here ... I've seen some (nasty) approaches for this with SignalR 1.1/1.2 ... but none for 2.0 yet.
Has anyone had any success with changing the SignalR 2.0 default json serializer to enable the…
typhoid
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11
votes
1 answer
invisible / hidden field in the constructor
I am ploughing through Learn You a Haskell for Great Good, and I have reached up to section 8.4, "Derived Instances". In this section, there's the following data type declaration:
data Person = Person { firstName :: String
,…
Optimight
- 2,809
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10
votes
2 answers
Derived type in PostgreSQL
Is it possible to create a "derived type" from a type? Like extends in Java.
For instance I need these types:
create type mytype as (
f1 int,
--many other fields...
fn varchar(10)
);
create type mytype_extended as (
f1 int,
…
bluish
- 23,093
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8
votes
2 answers
Type-bound procedure gives error about non-polymorphic passed-object dummy argument
I'm trying to compile the Fortran module below (using gfortran 7.2.0). The point is to define a derived type that in turn contains two instances of the derived type bspline_3d from the bspline-fortran library…
Tor
- 492
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- 15
6
votes
1 answer
Holding a pointer to a C function inside a Fortran derived type
I have a Fortran DLL which is called from a C program, and one of my procedures needs periodically to call a callback function which is supplied by the C program. I currently have it working well in its 'simple' form, but I'd like to be able to…
Eos Pengwern
- 1,215
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6
votes
4 answers
Named constants as components of a derived data type
It seems Fortran 90 does not allow named constants in derived data types. Is this true?
The following code does not work.
program my_prog
implicit none
type :: my_type
integer, parameter :: a = 1
real(kind(1.d0)) :: b
end type…
user1318806
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6
votes
2 answers
Using 2d array vs array of derived type in Fortran 90
Assuming you want a list of arrays, each having the same size. Is it better performance-wise to use a 2D array :
integer, allocatable :: data(:,:)
or an array of derived types :
type test
integer, allocatable :: content(:)
end type
type(test),…
alex_reader
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6
votes
2 answers
Can GDB be used to print values of allocatable arrays of a derived type in Fortran 90?
I have the following data structure in a Fortran90 program:
TYPE derivedType
CHARACTER(100) :: name = ' '
INTEGER :: type = 0
REAL(KIND(1.0D0)) :: property = 0.0
END TYPE derivedType
TYPE (derivedType), ALLOCATABLE,…
Neal Kruis
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5
votes
0 answers
Mapped types in Scala similar to Typescript Pick, Exclude, etc
Following on the heels of Mapped types in Scala
Is there a way to mimic Pick, Exclude, Diff and etc. from Typescript in Scala?
Using the a similar example as above:
case class Person(name: String, age: Int, address: String, phone: String)
is there…
Anton
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- 39
5
votes
2 answers
Constructor of derived types
I am trying to write a constructor for a derived type of an abstract one to solve this other question, but it seems that it's not working, or better, it isn't called at all.
The aim is to have a runtime polymorphism setting the correct number of…
senseiwa
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4
votes
0 answers
Using derived type member as a do loop iteration variable
EDIT: This has been marked as a duplicate of a question about using array elements to iterate a do loop. A similar question to be sure, but you can read the answers and not see anything about using non-array members of derived types. Even though…
bob.sacamento
- 5,295
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4
votes
2 answers
Write statement cannot produce new lines within user-defined formatted I/O procedures for derived type
I want to implement the user-defined I/O procedures for the derived types in my Fortran code. However, write statements within those procedures cannot produce new lines between two sequential write statements. The derived type and procedures are…
Rubin
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4
votes
0 answers
Sending derived-type with allocatable array between MPI process
For the context, in my CFD simulation, my computational domain is divided in blocks. Each block has its own number of cells, each one containing various information. Blocks are distributed among processes through a domain decomposition algorithm to…
Coriolis
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4
votes
1 answer
Fortran array of derived types and memory leaks despite finalization
I defined a derived type and encountered some problems with memory deallocation although I had written the final procedure. The code is as follows
module ModuleCoordinate
implicit none
type :: TCoordinate
real(8),dimension(:),pointer ::…
Waltergu
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