[stdlib_io] add `disp`(display variable values formatted). by zoziha · Pull Request #520 · fortran-lang/stdlib ·

@St-Maxwell

add disp.

Note: Because disp is a very important IO routine, I hope it will be discussed and approved more widely before it is adopted.

Description

Print your data to a output unit with a header. (more detail)

call [[stdlib_io(module):disp(interface)]]  &
( [x , header, unit=output_unit, brief=.false., format="g0.4", width=80, sep="  " ] )

Example:

use stdlib_strings, only: to_string
use stdlib_io,      only: disp, open

call disp("It is a note.")
call disp(x, "I am a scalar:")

i = open("array.txt")
call disp(A(1:50, 2:4), "Let me see the array:", unit=i, brief=.true.)
do j = 1, 3
    call disp(B(2:10,:,j), "Array B, index: "//to_string(j), unit=i)
end do
close(i)

Prior Art

keurfonluu/Forlab.disp
matlab.disp
armadillo/brief_print (good suggestion from @St-Maxwell )
ctsa/mdisplay

Notes

disp is the first routine I submitted to stdlib, because the original PR discussion became very long and not suitable for review (see #445).
And I resubmitted this PR now.

Thank you for this PR. Here are some comments on the specs.

doc/specs/stdlib_io.md

jvdp1 · 2021-10-02T18:05:16Z

doc/specs/stdlib_io.md

+
+### Arguments
+
+`x`: Shall be a `logical/integer/real/complex/string_type` scalar or `logical/integer/real/complex` and rank-1/rank-2 array.


Why not array of characters or of string_type?

The character length of array of string_type is often uncertain, and it is difficult to print them uniformly.
And we already have stringlist, its internal elements are private, and the outside is inaccessible.
(see stdlib_stringlist_type.f90#L52~L54)

Support for string_type type is added: string_type scalar, rank-1/rank-2 array.
Only character(*) scalar is supported, string_type array should be more easy to use than character(*) array.
:)

doc/specs/stdlib_io.md

I redesigned and updated the internal implementation of disp, it supports more control arguments, and now also supports the corresponding array of string_type type.
Therefore, poor internal design may be introduced. Please suggest amendments to make the disp more formal. 😊

Questions

width=80 by default.
Considering that disp has the need to output to the screen, 80 is a commonly used size.
Whether the outputted characters are left-justified (now solution) or right-justified (Pretty printing of matrices (and multidimensional arrays) #40 (comment))?
It seems that the left alignment needs to be neater.
Is the parameter sep required? How to determine the name sep?
sep(separator).
The compilation volume of the stdlib_io_disp.o submodule under gfortran has reached 800KB.
I have tried my best to improve it. If there is a way to improve the compilation volume, please let me know and I will try it.

Thank you :)

zoziha · 2021-11-09T14:51:56Z

src/stdlib_io_disp.fypp

+brief_ = optval(brief, .false.)
+format_ = optval(format, "g0.4")
+
+#! width have to be greater than or equal 80 by default


Suggested change
#! width have to be greater than or equal 80 by default
#! width have to be greater than or equal to 80 by default

…disp

Thank you for this proposition. Here are some comments.

Regarding the tests, I guess that they should be moved to support the test-drive features, introduced recently in stdlib. However, since this PR is open since a while, I would understand that you would prefer to not do it.

jvdp1 · 2021-11-24T19:02:02Z

doc/specs/stdlib_io.md

+- `x`: Shall be a `logical/integer/real/complex/character(len=*)/string_type` scalar or `logical/integer/real/complex/string_type` and rank-1/rank-2 array.
+This argument is `intent(in)` and `optional`.
+
+- `header`: Shall be a `character(len=*)` scalar.


Suggested change
- `header`: Shall be a `character(len=*)` scalar.
- `header`: Shall be a `character` scalar.

jvdp1 · 2021-11-24T19:02:19Z

doc/specs/stdlib_io.md

+This argument is `intent(in)` and `optional`.
+
+- `unit`: Shall be an `integer` scalar, linked to an IO stream.
+This argument is `intent(in)` and `optional`.<br>


Suggested change
This argument is `intent(in)` and `optional`.<br>
This argument is `intent(in)` and `optional`.

jvdp1 · 2021-11-24T19:02:41Z

doc/specs/stdlib_io.md

+The default value is `output_unit` from `iso_fortran_env` module.
+
+- `brief`: Shall be a `logical` scalar, controls an abridged version of the `x` array to be outputted.
+This argument is `intent(in)` and `optional`.<br>


Suggested change
This argument is `intent(in)` and `optional`.<br>
This argument is `intent(in)` and `optional`.

jvdp1 · 2021-11-24T19:02:52Z

doc/specs/stdlib_io.md

+This argument is `intent(in)` and `optional`.<br>
+The default value is `.false.`
+
+- `format`: Shall be a `character(len=*)` scalar.


Suggested change
- `format`: Shall be a `character(len=*)` scalar.
- `format`: Shall be a `character` scalar.

jvdp1 · 2021-11-24T19:03:02Z

doc/specs/stdlib_io.md

+The default value is `.false.`
+
+- `format`: Shall be a `character(len=*)` scalar.
+This argument is `intent(in)` and `optional`.<br>


Suggested change
This argument is `intent(in)` and `optional`.<br>
This argument is `intent(in)` and `optional`.

jvdp1 · 2021-11-24T19:04:44Z

doc/specs/stdlib_io.md

+
+- `sep`: Shall be a `character(len=*)` scalar, separator.
+This argument is `intent(in)` and `optional`.<br>
+The default value is "&ensp;&ensp;", two spaces.


What do you mean by two spaces?

jvdp1 · 2021-11-24T19:05:10Z

doc/specs/stdlib_io.md

+
+### Output
+
+The result is to print `header` and `x` on the screen (or another output `unit/file`) in this order.<br>


Suggested change
The result is to print `header` and `x` on the screen (or another output `unit/file`) in this order.<br>
The result is to print `header` and `x` on the screen (or another output `unit/file`) in this order.

jvdp1 · 2021-11-24T19:08:15Z

doc/specs/stdlib_io.md

+
+### Example
+
+```fortran


I suggest to reduce the example. One or two disp should be enough for the reader to understand its aim.

jvdp1 · 2021-11-24T19:09:37Z

src/stdlib_io.fypp

+!> version: experimental
+!>
+!> Display a scalar, vector or matrix formatted.
+!> ([Specification](../page/specs/stdlib_io.html#display-the-value-of-the-variable))


Suggested change
!> ([Specification](../page/specs/stdlib_io.html#display-the-value-of-the-variable))
!> ([Specification](../page/specs/stdlib_io.html#disp-display-the-value-of-the-variable))

jvdp1 · 2021-11-24T19:11:25Z

src/stdlib_io_disp.fypp

+width_ = optval(width, 80)
+width_ = merge(width_, 80, width_ > 80)
+
+sep_ = optval(sep, " ")


Why "two spaces" instead of "one space"?

Looking back at the content of this PR, it is rather complex and cumbersome. Now it will be migrated to #981 to continue, and this PR will be closed.

zoziha mentioned this pull request Sep 11, 2021
[stdlib_io] disp(display your data) #445
Closed
7 tasks

awvwgk linked an issue Sep 18, 2021that may be closed by this pull request
Pretty printing of matrices (and multidimensional arrays) #40
Open

awvwgk added reviewers neededThis requires extra eyestopic: IOCommon input/output related featureslabels Sep 18, 2021

add stdlib_io_disp.fypp.

f39b481

zoziha force-pushed the add_disp branch from 19dd5c6 to f39b481 Compare September 19, 2021 14:03

jvdp1 reviewed Oct 2, 2021
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zoziha marked this pull request as draft November 8, 2021 01:31

zoziha and others added 2 commits November 9, 2021 16:44

Merge branch 'master' into add_disp

38edc33

Redesign and update disp.

4bae170

zoziha force-pushed the add_disp branch from d4cce04 to a6b9e3e Compare November 9, 2021 11:46

zoziha changed the title ~~[stdlib_io] add disp(display your data).~~ [stdlib_io] add disp(display variable values formatted). Nov 9, 2021

zoziha force-pushed the add_disp branch from a6b9e3e to 18dd930 Compare November 9, 2021 11:51

Fix CI error: remove module keyword in submodule.

761dacf

zoziha force-pushed the add_disp branch from 18dd930 to 761dacf Compare November 9, 2021 12:32

Fix CI error: remove module keyword in submodule.

575c944

zoziha force-pushed the add_disp branch from 761dacf to 575c944 Compare November 9, 2021 14:11

zoziha marked this pull request as ready for review November 9, 2021 14:21

Minor fix.

fd00762

zoziha commented Nov 9, 2021
View reviewed changes

zoziha added 2 commits November 10, 2021 13:38

Merge branch 'add_disp' of https://.com/zoziha/stdlib into add_…

4299e5a
…disp

Ensure multi-thread safety.

710e115

zoziha marked this pull request as draft November 10, 2021 05:56

zoziha marked this pull request as ready for review November 10, 2021 05:59

jvdp1 reviewed Nov 24, 2021
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jvdp1 added the waiting for OPThis requires action from the OPlabel Dec 8, 2021

zoziha marked this pull request as draft December 14, 2021 10:21

zoziha mentioned this pull request Apr 20, 2025
stdlib_io: add print_array function to print arrays to output units #981
Open

zoziha closed this Apr 20, 2025

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		### Arguments

		`x`: Shall be a `logical/integer/real/complex/string_type` scalar or `logical/integer/real/complex` and rank-1/rank-2 array.

	#! width have to be greater than or equal 80 by default
	#! width have to be greater than or equal to 80 by default

	- `header`: Shall be a `character(len=*)` scalar.
	- `header`: Shall be a `character` scalar.

	This argument is `intent(in)` and `optional`.<br>
	This argument is `intent(in)` and `optional`.

	- `format`: Shall be a `character(len=*)` scalar.
	- `format`: Shall be a `character` scalar.


		### Output

		The result is to print `header` and `x` on the screen (or another output `unit/file`) in this order.<br>

	!> ([Specification](../page/specs/stdlib_io.html#display-the-value-of-the-variable))
	!> ([Specification](../page/specs/stdlib_io.html#disp-display-the-value-of-the-variable))

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Description

Prior Art

Notes

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