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[Plplot-cvs] SF.net SVN: plplot:[12846] trunk/doc/docbook/src/ada.xml
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From: <jb...@us...> - 2013-12-11 07:49:38
|
Revision: 12846
http://sourceforge.net/p/plplot/code/12846
Author: jbauck
Date: 2013-12-11 07:49:35 +0000 (Wed, 11 Dec 2013)
Log Message:
-----------
Update Ada documentation for new arrow-resetting feature and variant Ada-specific implementations
Modified Paths:
--------------
trunk/doc/docbook/src/ada.xml
Modified: trunk/doc/docbook/src/ada.xml
===================================================================
--- trunk/doc/docbook/src/ada.xml 2013-12-11 07:26:37 UTC (rev 12845)
+++ trunk/doc/docbook/src/ada.xml 2013-12-11 07:49:35 UTC (rev 12846)
@@ -1,6 +1,5 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!-- -*- mode: nxml -*- -->
-<!--
+<?xml version='1.0' encoding='UTF-8'?>
+<!-- -*- mode: nxml -*- --><!--
ada.xml: "Ada Language" chapter
Copyright (C) 2008-2010 Jerry Bauck
@@ -31,27 +30,20 @@
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION,
EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
--->
-<!--
-Note to self: Uncomment these lines when editing with Serna or XMLmind.
-<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
-"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
--->
+--><!-- Note to self: Uncomment these lines when editing with Serna or XMLmind
+ or whatever, a validity check doesn't always fail. --><!-- This document was created with Syntext Serna Free. -->
+<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" []>
<chapter id="ada">
<title>Ada Language</title>
-
<para>This document describes the Ada bindings to the PLplot technical
plotting software, how to obtain the necessary software components, and how
to use them together.</para>
-
<sect1 id="ada_overview">
<title>Overview</title>
-
<para>The Ada bindings for PLplot provide a way for Ada programmers to
access the powerful PLplot technical plotting facilities directly from Ada
programs while working completely in Ada; the Ada programmer never needs
to know or worry that PLplot itself is written in another language.</para>
-
<para>There are a thin binding and two thick bindings provided. The thin
binding presents the application programming interface (API) in a form
very similar to the C API, although in 100% Ada. The thick bindings
@@ -59,30 +51,24 @@
and add some ease-of-use features. It is expected that the thick bindings
will be preferred.</para>
</sect1>
-
<sect1 id="ada_bindings">
<title>The Bindings</title>
-
<para>The bindings are a re-expression and extension of the C-language API
- and as such are a kind of abstract layer between the user's code and the
+ and as such are a kind of abstract layer between the user's code and the
PLplot binary library. Additionally, there are a few capabilities not in
the official API but nonetheless which are available to the C programmer
which are included in the bindings and thus are directly available to the
Ada programmer.</para>
-
<para>The thin binding is a layer between the thick bindings and the
underlying C code. It is mainly a programming convenience for the
developer of the bindings; this is a common implementation for foreign
language bindings and for the most part, the user can ignore it.</para>
-
<para>There are two thick bindings provided for the convenience of the
user. Either may be used and they both provide exactly the same
- functionality. The thick bindings are the user's main concern with
+ functionality. The thick bindings are the user's main concern with
programming for PLplot.</para>
-
<sect2 id="ada_thin">
<title>Thin Binding</title>
-
<para>The thin binding, in the files <literal>plplotthin.ads</literal>
and <literal>plplotthin.adb</literal>, is mostly a direct and obvious
mapping of the C application programming interface (API) to Ada. Thus,
@@ -93,21 +79,18 @@
color using a number which is associated with a set of colors.) Various
constants from the C API are also included here. Numeric types as
defined in PLplot are associated with numeric types in Ada in the thin
- binding by use of Ada's type system. Thus, the thin binding refers to
+ binding by use of Ada's type system. Thus, the thin binding refers to
the PLplot-centric type <literal>PLFLT</literal> for floating-point
types while the thick binding uses the usual Ada type
<literal>Long_Float</literal>.</para>
-
<para>Many of the comments from the C source header file (similar in
purpose to an Ada specification file) have been retained in the thin
binding, even when they are no longer make sense. These might be pruned at
some point to facilitate reading the Ada source.</para>
-
<para>Also included in the thin binding are some other declarations
which help the Ada binding to mesh well with C by emulating certain data
structures which are needed in some rather specialized usages as well as
providing certain subprogram pointer types.</para>
-
<para>The Ada programmer working with either of the thick bindings will
have to refer to the thin binding relatively rarely, if ever, and mainly
to examine the subroutine pointer declarations and the several variant
@@ -118,40 +101,34 @@
everything of interest to the user in the thick bindings and the user
need not bother with the thin binding.</para>
</sect2>
-
<sect2 id="ada_thick">
<title>The Thick Bindings</title>
-
<para>The thick bindings provide most of the information that the Ada
programmer needs. Normally, only one of the two thick bindings would be
used per user program but it should be possible to include both but that
scenario would be unusual.</para>
-
<para>There are three main aspects of the thick bindings: providing an
alternative access to the PLplot API, extending the PLplot functionality
with some easy-to-use features, and overlaying Ada data structures and
types.</para>
-
<para>In the first aspect, the thick bindings provide a fully Ada
interface to the entire PLplot library. Packages are
<literal>with</literal>-ed and <literal>use</literal>-d as normal Ada
code. Ada arrays can be passed as usual, not requiring the array length
or start or end indices to be passed separately. All necessary Ada types
are made to match the underlying C types exactly.</para>
-
<para>The second aspect of the thick bindings is to provide some
simplified ways to get a lot of plotting done with only one or two
subroutine calls. For example, a single call to Simple_Plot can display
- from one to five "<emphasis>y</emphasis>'s" as a function of a single
- "<emphasis>x</emphasis>" with default plot appearances chosen to suit
+ from one to five "<emphasis>y</emphasis>'s" as a function of a single
+ "<emphasis>x</emphasis>" with default plot appearances chosen to suit
many situations. Other simple plotters are available for
- three-dimensional and contour plots. Manipulating PLplot's colors is
+ three-dimensional and contour plots. Manipulating PLplot's colors is
similarly made easy and some default color schemes are provided.</para>
-
<para>The third main aspect of the thick binding is to use Ada data
- structures and Ada's type system extensively to reduce the chances of
+ structures and Ada's type system extensively to reduce the chances of
inappropriate actions. For example, Ada arrays are used throughout (as
- opposed to C's
+ opposed to C's
pointer-plus-offset-while-carrying-along-the-size-separately approach).
Quantities which have natural range limits are
<literal>subtype</literal>-d to reflect those constraints. The hope is
@@ -160,19 +137,16 @@
reports at all. However, there remain a few instances where the typing
could be improved and PLplot errors will still be reported from time to
time.</para>
-
<para>Both the specification and body for the standard thick (and thin)
binding contain the C subroutine name as a comment line immediately
above the Ada procedure declaration; this should help in making the
- associations between "Ada" names and "PLplot" names. Also, the
+ associations between "Ada" names and "PLplot" names. Also, the
subroutine-specific comments from the C API have been retained
verbatim.</para>
</sect2>
-
<sect2 id="ada_thick_enhanced">
<title>Standard Thick Binding Using Enhanced Names</title>
-
- <para>The distinguishing feature of this thick binding (the "standard"
+ <para>The distinguishing feature of this thick binding (the "standard"
binding) is to provide more descriptive names for PLplot subroutines,
variables, constants, arguments, and other objects. Most Ada programmers
will be more comfortable using these names. For example, in the C API as
@@ -185,13 +159,12 @@
<literal>1</literal>. Many such numeric constants from the C API are
given names in this thick binding. These renamed integers are discussed
more fully in Section 7.2.</para>
-
<para>The disadvantage of this renaming is that it makes referring to
the PLplot documentation somewhat awkward. There might be, at some time,
a utility for easing this problem by providing an HTML file with links
- so that a "normal" PLplot name can be linked to the "Ada" name along
+ so that a "normal" PLplot name can be linked to the "Ada" name along
with the appropriate entry in the Ada specification, as well as another
- HTML file with links from the "Ada" name directly to the PLplot web page
+ HTML file with links from the "Ada" name directly to the PLplot web page
that documents that name. It might also be possible to provide an
alternate version of the documentation with the enhanced names used.
(The developer of the bindings has a sed file prepared which makes most
@@ -199,34 +172,27 @@
retains the original C subprogram names as comments immediately above
the function or procedure name in the code listing so it is relatively
easy to locate the relevant item in the PLplot documentation.</para>
-
<para>One simple rule applies in reading the PLplot API documentation:
the argument names are in the same order in Ada as in the PLplot
documentation (the names are different) except that all array lengths
are eliminated. The PLplot documentation, for each subroutine, shows a
- "redacted" version which should be correct for Ada as well as other
+ "redacted" version which should be correct for Ada as well as other
languages which have proper arrays.</para>
-
<para>The standard bindings are in the Ada files
<literal>plplot.ads</literal> and <literal>plplot.adb</literal>.</para>
</sect2>
-
<sect2 id="ada_thick_traditional">
<title>Thick Binding Using Traditional Names</title>
-
<para>This thick binding provides exactly the same functionality as the
standard thick binding but retains the original names as used in the C
code and the PLplot documentation.</para>
-
<para>The traditional bindings are in the Ada files
<literal>plplot_traditional.ads</literal> and
<literal>plplot_traditional.adb</literal>.</para>
</sect2>
</sect1>
-
<sect1 id="ada_examples">
<title>The Examples</title>
-
<para>An important part of the Ada bindings is the examples, some 33 of
which demonstrate how to use many of the features of the PLplot package.
These examples also serve as a test bed for the bindings in Ada and other
@@ -235,21 +201,17 @@
been completely re-written in Ada (but retain a C flavor in the names that
are given to objects). All of the Ada examples generate exactly the same
Postscript as the C versions, Examples 14 and 17 excepted since those
- operate interactively and don't (normally) make Postscript. Two versions
+ operate interactively and don't (normally) make Postscript. Two versions
of each example are available, one calling the standard binding and the
other the traditional binding. (In development, a sed script does almost
all of the conversion automatically.)</para>
</sect1>
-
<sect1 id="ada_obtaining">
<title>Obtaining the Software</title>
-
<para>There are three software components that you will need: an Ada
compiler, the PLplot library, and the Ada bindings.</para>
-
<sect2 id="ada_obtaining_ada">
<title>Obtaining an Ada compiler</title>
-
<para>You will need an Ada compiler in order to use the Ada PLplot
bindings. There are several compilers available. Here, we will focus on
the free, open source compiler that is included with the GNU Compiler
@@ -259,35 +221,27 @@
was originally developed at NYU, it has for many years been developed
and supported commercially by AdaCore with academic and pro versions
available.)</para>
-
<para>Your computer may already have GNAT installed, or you can download
it from <ulink url="http://gcc.gnu.org/">gcc.gnu.org</ulink>. Another
- route to obtaining GNAT is from the AdaCore page, <ulink
- url="https://libre2.adacore.com/">libre2.adacore.com</ulink>. There are
- versions for many operating systems and processors including Apple's OS
+ route to obtaining GNAT is from the AdaCore page, <ulink url="https://libre2.adacore.com/">libre2.adacore.com</ulink>. There are
+ versions for many operating systems and processors including Apple's OS
X or its open source version Darwin, Linux, and Windows. The gcc and
AdaCore versions differ in their licenses. Download the version that you
need and follow the installation instructions.</para>
</sect2>
-
<sect2 id="ada_obtaining_plplot">
<title>Download and install PLplot</title>
-
- <para>PLplot can be downloaded from the PLplot project page at <ulink
- url="http://sourceforge.net/projects/plplot">sourceforge.net</ulink>.
+ <para>PLplot can be downloaded from the PLplot project page at <ulink url="http://sourceforge.net/projects/plplot">sourceforge.net</ulink>.
Follow the installation instructions after downloading. The installation
process requires that your computer has CMake installed. OS X users can
try installing PLplot in its entirety from MacPorts. The advantage of
using MacPorts is that all installation dependencies are automatically
installed for you.</para>
</sect2>
-
<sect2 id="ada_obtaining_bindings">
<title>The Ada bindings to PLplot</title>
-
<para>The third major software component is the bindings themselves;
they are included with the PLplot software itself.</para>
-
<para>The bindings themselves are six Ada source files named (using GNAT
filename extensions) <literal>plplot.ads</literal>,
<literal>plplot.adb</literal>,
@@ -299,23 +253,18 @@
later, in Section 9.</para>
</sect2>
</sect1>
-
<sect1 id="ada_howto">
<title>How to use the Ada bindings</title>
-
<sect2 id="ada_95_2005">
<title>Ada 95 versus Ada 2005</title>
-
<para>The bindings will work for either Ada 95 or Ada 2005 but there is
a slightly subtle point regarding the use and declaration of vectors and
matrices. The package <literal>PLplot_Auxiliary</literal> declares the
types</para>
-
<programlisting>
type Real_Vector is array (Integer range <>) of Long_Float;
type Real_Matrix is array (Integer range <>, Integer range <>) of Long_Float;
</programlisting>
-
<para>These declarations mimic exactly the declarations described in
Annex G.3, Vector and Matrix Manipulation, of the Ada 2005 reference
manual when the generic package therein described is specialized for
@@ -324,7 +273,6 @@
<literal>Ada.Numerics.Long_Real_Arrays</literal> simply to gain access
to these types and in the process require linking to the BLAS and LAPACK
numerical libraries.</para>
-
<para>Ada 2005 introduced an annex G.3 which formally defines vector and
matrix support to Ada, along with some common mathematical operations on
those types. (This feature is a specific to vectors and matrices and
@@ -341,16 +289,13 @@
depending on the Cmake configuration to expose a 2005 compiler in the later
case. (Note that at some points in the documentation, Ada 2005 is referred
to as Ada 2007, including some Cmake flags.)</para>
-
<para>This policy was changed in SVN version 11153. Before this, the
type of compiler (Ada 95 or Ada 2005) had to be specified at the time
that PLplot was built, and in the case of Ada 2005, the BLAS and LAPACK
libraries had to be present and were subsequently linked.</para>
</sect2>
-
<sect2 id="ada_gnat_nongnat">
<title>GNAT versus non-GNAT</title>
-
<para>The bindings were made using the GNAT compiler and there is a
slight dependence on that compiler. Specifically, the
<literal>Unrestricted_Access</literal> attribute of GNAT was used in
@@ -360,44 +305,35 @@
(2D array) is passed to a PLplot subroutine. For more about
<literal>Unrestricted_Access attribute</literal>, see Implementation
Defined Attributes in the GNAT Reference Manual. This dependency
- shouldn't be difficult to remove by either incorporating the GNAT code
+ shouldn't be difficult to remove by either incorporating the GNAT code
which implements it, by following the TO-DO comment near the function
definition in <literal>plplotthin.adb</literal>, or by providing the
proper aliasing.</para>
-
<para>Another GNAT dependency is used to parse command line arguments in
a C-like way.</para>
-
- <para>Pragma Warnings (Off, "some text") and Pragma Warnings (On, "some
- text") are used in the bindings to suppress warnings about a particular
+ <para>Pragma Warnings (Off, "some text") and Pragma Warnings (On, "some
+ text") are used in the bindings to suppress warnings about a particular
method used to interface with C code. These pragmas are also used in
Ada Examples 21 to suppress a particular warning. Pragma Warnings is a
GNAT extension. Non-GNAT usage could simply remove these pragmas with
the resulting warnings ignored as they are benign.</para>
-
<para>Most of the GNAT dependencies can be found by searching the source
- code for "<literal>GNAT</literal>",
- "<literal>Unrestricted_Access</literal> and <literal>Pragma
- Warnings</literal>."</para>
-
+ code for "<literal>GNAT</literal>",
+ "<literal>Unrestricted_Access</literal> and <literal>Pragma Warnings</literal>."</para>
<para>The GNAT dependence, though slight, will no doubt frustrate users
of other Ada compilers. We welcome comments from those users, especially
comments with specific suggestions on how to remove any GNAT-specific
usages.</para>
</sect2>
-
<sect2 id="ada_sample_project">
<title>Sample command line project</title>
-
<para>It is instructive to present a simple example that can be compiled
and run from the command line. Although this example is specific to one
installation, it should be fairly straightforward to adapt it to another
installation. Toward that end, it is helpful to understand the PLplot
- lingo of "build directory" and "installation directory."</para>
-
+ lingo of "build directory" and "installation directory."</para>
<para>Here is a simple program that will generate a plot of part of a
parabola.</para>
-
<programlisting>
with
PLplot_Auxiliary,
@@ -408,7 +344,7 @@
procedure Simple_Example is
x, y : Real_Vector(-10 .. 10);
begin
- for i in x'range loop
+ for i in x'range loop
x(i) := Long_Float(i);
y(i) := x(i)**2;
end loop;
@@ -417,7 +353,6 @@
End_PLplot; -- Call this only once.
end Simple_Example;
</programlisting>
-
<para>Next is a bash script that will compile, bind, and link it. It is
installation-specific in that paths to the GNAT compiler, PLplot
libraries, and BLAS (Basic Linear Algebra System) and LAPACK (Linear
@@ -425,13 +360,11 @@
fit your installation. Some Linux installations which have GNAT 4.3 or
later (Ada 2005) pre-installed might have already set the paths to the
BLAS and LAPACK libraries.</para>
-
<para>(Note that the G.3 Annex of Ada 2005, in the GNAT version, depends
heavily on BLAS and LAPACK. These packages are tried-and-true packages
that are available from several places in either C or Fortran versions.
The present example is specific to OS X which has both C and Fortran
versions pre-installed.)</para>
-
<programlisting>
#!/bin/bash
/usr/local/ada-4.3/bin/gnatmake simple_example.adb \
@@ -442,32 +375,25 @@
/Developer/SDKs/MacOSX10.4u.sdk/usr/lib/libblas.dylib \
/Developer/SDKs/MacOSX10.4u.sdk/usr/lib/liblapack.dylib
</programlisting>
-
<para>The resulting binary program can be run by typing
<command>./simple_example</command></para>
</sect2>
</sect1>
-
<sect1 id="ada_unique">
<title>Unique Features of the Ada bindings</title>
-
<para>The Ada bindings have been augmented with a number of features which
are intended to simplify the use of PLplot. They include high-level
features for simplified plotting (such as easy foreground-background
- control, a collection of "simple plotters," and easy color map
+ control, a collection of "simple plotters," and easy color map
manipulations), integer options which have been given meaningful names,
and a few other focused additions. Many users will find that they can do
- most of their work using the "simple plotters".</para>
-
+ most of their work using the "simple plotters".</para>
<sect2 id="ada_high_level">
<title>High-level features for simplified plotting</title>
-
<sect3 id="ada_foreground_background">
<title>Foreground-background control</title>
-
<sect4 id="ada_draw_bw">
<title>Draw_On_Black, Draw_On_White</title>
-
<para>The default for PLplot is to draw its graphics on a black
background. A white background can be used instead with
<literal>Draw_On_White</literal> or reset to the original mode with
@@ -478,92 +404,68 @@
background.</para>
</sect4>
</sect3>
-
<sect3 id="ada_simple_plotters">
<title>Simple Plotters</title>
-
<para>Several high-level but flexible plotters are available and more
might be added in the future. It is expected that many users will find
that these high-level routines are adequate for most of their
day-to-day plotting.</para>
-
<sect4 id="ada_multiple_pairs">
<title>Multiplot_Pairs</title>
-
<para>Plot up to five <emphasis>x-y</emphasis> pairs with easy
labelling, coloring, line width and styles, justification, and
zooming.</para>
</sect4>
-
<sect4 id="ada_simple_plot">
<title>Simple_Plot</title>
-
- <para>Plot up to five <emphasis>y</emphasis>'s against a single
+ <para>Plot up to five <emphasis>y</emphasis>'s against a single
<emphasis>x</emphasis> with easy labelling and automatic line colors
and styles.</para>
</sect4>
-
<sect4 id="ada_simple_plot_logx">
<title>Simple_Plot_Log_X</title>
-
<para>Same as <literal>Simple_Plot</literal> but with logarithmic
<emphasis>x</emphasis>-axis.</para>
</sect4>
-
<sect4 id="ada_simple_plot_logy">
<title>Simple_Plot_Log_Y</title>
-
<para>Same as <literal>Simple_Plot</literal> but with logarithmic
<emphasis>y</emphasis>-axis.</para>
</sect4>
-
<sect4 id="ada_simple_plot_logxy">
<title>Simple_Plot_Log_XY</title>
-
<para>Same as <literal>Simple_Plot</literal> but with logarithmic
<emphasis>x</emphasis>- and <emphasis>y</emphasis>-axes.</para>
</sect4>
-
<sect4 id="ada_simple_plot_pairs">
<title>Simple_Plot_Pairs</title>
-
<para>Plot up to five <emphasis>x</emphasis>-<emphasis>y</emphasis>
pairs with easy labelling and automatic line colors and
styles.</para>
</sect4>
-
<sect4 id="ada_single_plot">
<title>Single_Plot</title>
-
<para>Plot a single <emphasis>x</emphasis>-<emphasis>y</emphasis>
pair with flexible labels, axis styles, colors, line width and
style, justification, and zooming.</para>
</sect4>
-
<sect4 id="ada_simple_contour">
<title>Simple_Contour</title>
-
<para>Make a contour plot with labels</para>
</sect4>
-
<sect4 id="ada_simple_mesh">
<title>Simple_Mesh_3D</title>
-
<para>Easy 3D mesh plot with labels, zooming, and perspective
controls</para>
</sect4>
-
<sect4 id="ada_simple_surface_3d">
<title>Simple_Surface_3D</title>
-
<para>Easy 3D surface plot with labels, zooming, and perspective
controls</para>
</sect4>
</sect3>
-
<sect3 id="ada_simple_color">
<title>Simple color map manipulations</title>
-
<para>PLplot provides extensive manipulation and control of two
separate color maps, color map 0 and color map 1. The Ada binding
makes basic manipulations easier and also adds facilities for making
@@ -571,7 +473,6 @@
restored later. An initial snapshot is taken when the package is
initialized so that the default color settings can always be restored
after having been changed.</para>
-
<para>Another set of features lets the user reset the 16 individual
colors in color map 0 after a color definition has been changed. It is
important to note that while <literal>Set_Pen_Color(Red)</literal>
@@ -582,203 +483,143 @@
<literal>Set_Pen_Color(Red)</literal> will draw in that color instead
of red. To always assure that red is drawn even if the color map has
been changed for integer <literal>1</literal>, use
- <literal>Set_Pen_Color(Reset_Red)</literal> instead. These 16 "reset"
+ <literal>Set_Pen_Color(Reset_Red)</literal> instead. These 16 "reset"
functions return the appropriate default integer for the specified
color but also reset that slot in the color table so that a subsequent
call such as <literal>Set_Pen_Color(Red)</literal> will also cause
drawing in red.</para>
-
<para>Color map 1 also gets a easy-to-use makeover for Ada users.
There are several pre-built color themes that are useful for quickly
making surface and mesh plots,
<literal>Color_Themes_For_Map_1_Type</literal>. These color themes can
be quickly applied with
<literal>Quick_Set_Color_Map_1</literal>.</para>
-
<para>Miscellaneous other Ada features include a pre-built mask
function for <literal>Shade_Regions</literal> that does no masking;
perhaps the most useful purpose is to provide a template for writing
mask functions that do mask. And there is a handy function for
calculating the contour levels for making contour plots.</para>
-
<itemizedlist>
<listitem>
<para>Color table snapshots</para>
-
<para><literal>Make_Snapshot_Of_Color_Map_0</literal></para>
-
<para><literal>Restore_Snapshot_Of_Color_Map_0</literal></para>
-
<para><literal>Restore_Default_Snapshot_Of_Color_Map_0</literal></para>
</listitem>
-
<listitem>
<para>Color resetting functions for the 16 colors of color map
0</para>
-
<para><literal>Reset_Black, Reset_Red, ..., Reset_White</literal></para>
</listitem>
-
<listitem>
<para>Easy manipulation of color map 1</para>
-
<para>Pre-built color themes for color map 1:
<literal>Color_Themes_For_Map_1_Type</literal></para>
-
<para>Quick application of pre-built color themes:
<literal>Quick_Set_Color_Map_1</literal></para>
</listitem>
-
<listitem>
<para>Other features</para>
-
<para>A pre-built mask function for
<literal>Shade_Regions</literal> that does no masking:
<literal>Mask_Function_No_Mask</literal></para>
-
<para>An easy way to calculate an array of contour levels for
contour plots: <literal>Calculate_Contour_Levels</literal></para>
</listitem>
</itemizedlist>
</sect3>
</sect2>
-
<sect2 id="ada_integer_options">
<title>Integer Options Given Ada Names</title>
-
<para>The C version of PLplot uses a number of integers to mean specific
things. Unfortunately, the meaning is lost when it it consigned to being
a mere integer with no name. The Ada binding partially rectifies this
situation by giving names to these integer constants. The integer can
still be used if desired. (A more complete and safer rectification would
use enumerated types.)</para>
-
<para>Below is a listing of at least the contexts in which these
- "re-namings" have been applied. In some cases the entire range of values
+ "re-namings" have been applied. In some cases the entire range of values
is listed, but if there are more than about four such values for each
context, only a sampling is given.</para>
-
<para><emphasis role="bold"> Instances</emphasis></para>
-
<para><itemizedlist>
<listitem>
<para>Colors: Plot_Color_Type</para>
-
<para><literal> 0</literal> is Black, <literal>1</literal> is Red,
etc</para>
</listitem>
-
<listitem>
<para>Justification for plots:
<literal>Justification_Type</literal></para>
-
<para><literal>User_Justified</literal></para>
-
<para><literal>Not_Justified</literal></para>
-
<para><literal>Justified</literal></para>
-
<para><literal>Justified_Square_Box</literal></para>
</listitem>
-
<listitem>
<para>Axis styles: <literal>Axis_Style_Type</literal></para>
-
<para><literal>Linear_Major_Grid</literal></para>
-
<para><literal>Linear_Minor_Grid</literal></para>
-
<para>etc.</para>
</listitem>
-
<listitem>
<para>Font styles: <literal>Font_Style_Type</literal></para>
-
<para><literal>Normal_Font</literal></para>
-
<para><literal>Roman_Font</literal></para>
-
<para><literal>Italic_Font</literal></para>
-
<para><literal>Script_Font</literal></para>
</listitem>
-
<listitem>
<para>Character sets: <literal>Character_Set_Type</literal></para>
-
<para><literal>Standard_Character_Set</literal></para>
-
<para><literal>Extended_Character_Set</literal></para>
</listitem>
-
<listitem>
<para>Plot orientation: <literal>Orientation_Type</literal></para>
-
<para><literal>Landscape</literal></para>
-
<para><literal>Portrait</literal></para>
</listitem>
-
<listitem>
<para>Modes for parsing command line arguments:
<literal>Parse_Mode_Type</literal></para>
-
<para>E.g. <literal>PL_PARSE_PARTIAL</literal></para>
</listitem>
-
<listitem>
<para>Descriptions of map outlines (continents, states, etc.):
<literal>Map_Type</literal></para>
-
<para><literal>Continents</literal></para>
-
<para><literal>USA_and_States</literal></para>
-
<para><literal>Continents_and_Countries</literal></para>
-
<para><literal>USA_States_and_Continents</literal></para>
</listitem>
-
<listitem>
<para>Various style and view options for 3D and surface
plots</para>
-
<para>E.g. <literal>Lines_Parallel_To_X</literal></para>
</listitem>
-
<listitem>
<para>Kind of gridding algorithm for interpolating 2D data to a
grid: <literal>Gridding_Algorithm_Type</literal></para>
-
<para>E.g.
<literal>Grid_Bivariate_Cubic_Spline_Approximation</literal></para>
</listitem>
-
<listitem>
<para>Flags for histogram style</para>
-
<para>E.g. <literal>Histogram_Default</literal></para>
</listitem>
-
<listitem>
<para>Flags for histogram binning</para>
-
<para>E.g. <literal>Bin_Default</literal></para>
</listitem>
-
<listitem>
<para>Names for color space models</para>
-
<para>Hue, Lightness, Saturation: <literal>HLS</literal></para>
-
<para>Red, Green, Blue: <literal>RGB</literal></para>
</listitem>
</itemizedlist></para>
</sect2>
-
<sect2 id="ada_one_offs">
<title>One-offs</title>
-
<para>To provide convenient string handling in a fashion that is
familiar to Ada programmers, function versions which return a
<literal>String</literal> type are provided of
@@ -788,7 +629,6 @@
<literal>plgver</literal>, and <literal>plgfnam</literal> in the
traditional binding). These functions replace the procedure-style
subprograms that are described in the C API documentation.</para>
-
<para>Overloaded <literal>Set_Line_Style</literal>
(<literal>plstyl</literal> in the traditional binding) with a version
that takes a single argument,
@@ -796,12 +636,10 @@
situation of calling the normal versions of these procedures with unused
arguments simply to set the line style to the default, continuous,
line.</para>
-
<para>The contour plotter <literal>Contour_Plot_Irregular_Data</literal>
(<literal>plfcont</literal> in the traditional binding) is provided for
making contour plots from irregularly spaced data. This feature is not
documented in the PLplot API documentation.</para>
-
<para>The custom label function <literal>Set_Custom_Label</literal>
(<literal>plslabelfunc</literal> in the traditional binding) can be
called with null arguments to revert to using the default labelling
@@ -809,7 +647,6 @@
<literal>Use_Default_Labels</literal>, is provided. See Ada example 19
(<literal>x19a.adb</literal> or <literal>xthick19a.adb</literal>) for a
usage example.</para>
-
<para>The custom coordinate transform setter,
<literal>Set_Custom_Coordinate_Transform</literal>,
(<literal>plstransform</literal> in the traditional binding) can be
@@ -819,54 +656,55 @@
arguments, <literal>Clear_Custom_Coordinate_Transform</literal>, is
provided. See Ada example 19 (<literal>x19a.adb</literal> or
<literal>xthick19a.adb</literal>) for a usage example.</para>
+ <para>The procedure <literal>Set_Arrow_Style_For_Vector_Plots</literal>
+ (<literal>plsvect</literal> in the traditional binding) normally is called
+ to define the shape of an arrow in vector plots. However, calling it with
+ null pointer arguments (<literal>System.Null_Address</literal>) in place
+ of the <literal>Real_Vector</literal> arrays and <literal>False</literal>
+ for the <literal>Fill_Arrow</literal> argument causes the arrow shape to
+ be reset to the default shape; this is implemented in Ada as an overloaded
+ procedure in order to be consistent with the C API but is rather awkward.
+ So there are two additional procedures that are added for the convenience
+ of Ada programmers: Reset_Vector_Arrow_Style and plsvect, both without
+ arguments, both available in both bindings, and the latter an overload of
+ the normal arrow-setting procedure.</para>
</sect2>
</sect1>
-
<sect1 id="ada_c_flavor">
<title>Parts That Retain a C Flavor</title>
-
<para>There remains at least one area in the Ada bindings which is still
affected by the C underpinnings. This might be cleaned up in future
versions. There might be other residual C influence as well.</para>
-
<sect2>
<title>Map-drawing</title>
-
<para><literal>plmapform</literal> as called by
<literal>Draw_Latitude_Longitude</literal> (<literal>plmap</literal>)
and <literal>Draw_Latitude_Longitude</literal>
(<literal>plmeridians</literal>)</para>
-
<para>This is the only place in the PLplot bindings where a C subprogram
calls an Ada subprogram while passing an array. If the array is
unconstrained, there is no guarantee that it will work because C has no
way of telling Ada what offset to use for the beginning of the array.
But passing a constrained array is acceptable with the downside that the
array size must be fixed within the bindings as being large enough to
- handle any situation; currently, it is sized as <literal>0 ..
- 2000</literal>. See Example 19 for how this is handled in by the user
+ handle any situation; currently, it is sized as <literal>0 .. 2000</literal>. See Example 19 for how this is handled in by the user
program. The constrained array is called
<literal>Map_Form_Constrained_Array</literal>.</para>
</sect2>
</sect1>
-
<sect1 id="ada_known_variances">
<title>Known Variances</title>
-
<sect2>
<title>Documentation</title>
-
<para>In numerous places in the documentation, a feature is listed or
- described as "C only." Many of these features are actually available in
+ described as "C only." Many of these features are actually available in
Ada. For example, in <literal>Contour_Plot</literal>
(<literal>plcont</literal> in the traditional binding), the
transformation from array indices to world coordinates is mentioned as
- "C only" but is actually available in Ada.</para>
+ "C only" but is actually available in Ada.</para>
</sect2>
-
<sect2>
<title>API</title>
-
<para>The C documentation for <literal>plscmap1l</literal>,
(<literal>Set_Color_Map_1_Piecewise</literal> in the thick binding) and
<literal>plscmap1la</literal>
@@ -875,40 +713,32 @@
behavior is as though a proper-length array of all
<literal>False</literal> values was passed. In Ada, these procedures are
overloaded to allow a last argument that can be either an array of
- Boolean or a value of the enumerated type <literal>type Alt_Hue_Path_Type is (Alt_Hue_Path_None,
- Alt_Hue_Path_All)</literal>.</para>
+ Boolean or a value of the enumerated type <literal>type Alt_Hue_Path_Type is (Alt_Hue_Path_None, Alt_Hue_Path_All)</literal>.</para>
</sect2>
</sect1>
-
<sect1 id="ada_compilation_notes">
<title>Compilation notes</title>
-
<sect2>
<title>Ada 95 Versus Ada 2005</title>
-
<para>As discussed in Section 6.1, the bindings are made to work with
Ada 95 and Ada 2005, but special steps need to be taken in order to
access the numerical capabilities of Ada 2005 to the extent that vectors
and arrays of the type defined in the Ada Reference Manual Annex G.3 are
required to be passed to PLplot routines.</para>
</sect2>
-
<sect2>
<title>GNAT Dependence</title>
-
<para>There is a slight but significant dependence on the GNAT version
of Ada. This is discussed more fully in Section 6.2</para>
</sect2>
-
<sect2>
<title>PLplot_Auxiliary</title>
-
<para>The bindings include files <literal>PLplot_Auxiliary.ads</literal>
and <literal>PLplot_Auxiliary.adb</literal>. These files are currently
used to provide a few convenience subprograms that are used in the
examples. However, they are also associated with the above-mentioned
facility to easily accommodate accessing the G.3 Annex vector-matrix
- manipulation facilities. If not for the desire for this easy "switching"
+ manipulation facilities. If not for the desire for this easy "switching"
ability, the <literal>PLplot_Auxiliary</literal> package could be
removed from the <literal>with</literal> parts of the other binding
files. Even so, it could be still removed with minor modifications to
@@ -917,74 +747,56 @@
referenced by most of the Ada examples.</para>
</sect2>
</sect1>
-
<sect1 id="ada_apple_notes">
<title>Notes for Apple Macintosh OS X users</title>
-
<para>The following comments apply to users of Apple Macintosh computers
- which run OS X. OS X users may use Apple's free integrated development
+ which run OS X. OS X users may use Apple's free integrated development
environment (IDE) or may prefer other methods such as using a favorite
editor and building from the command line.</para>
-
<para>OS X users should be aware that an excellent graphical terminal
program is available and is highly recommended. It is called AquaTerm and
is a full Cocoa program with window control. Performing a cut operation
places a PDF of the front window on the clipboard, a convenience when
working with other graphics or word processing programs.</para>
-
<sect2>
- <title>Using Apple's Xcode IDE</title>
-
- <para>The Macintosh Ada community has made a plug-in for Apple's free
+ <title>Using Apple's Xcode IDE</title>
+ <para>The Macintosh Ada community has made a plug-in for Apple's free
Xcode integrated development environment (IDE) that makes programming
Ada in Xcode possible. The plug-in is included with the compiler that is
available at <ulink url="http://www.macada.org/">www.macada.org</ulink>.
Since Xcode is based on gcc, it is possible to work in the various gcc
languages as well as to incorporate binaries such as the PLplot
library.</para>
-
<para>In order to make an Xcode project, drag-and-drop source files and
the PLplot library file to the Groups & Files pane of an Ada
project. There are a few idiosyncrasies that you may encounter so make
- sure to contact the very friendly Macintosh Ada mailing list at <ulink
- url="http://www.macada.org/">www.macada.org</ulink> or study the FAQ at
+ sure to contact the very friendly Macintosh Ada mailing list at <ulink url="http://www.macada.org/">www.macada.org</ulink> or study the FAQ at
that same site if you have any difficulties.</para>
-
<para>[This plug-in still works for some older versions of Xcode but not
- for newer versions, as of 2013.]</para>
+ for newer versions, as of 2013.]</para>
</sect2>
-
<sect2>
<title>AquaTerm</title>
-
<para>AquaTerm is a display option available on Macintosh computers
using OS X and is supported by PLplot. It is a native Cocoa graphics
- "terminal" that is highly recommended. All output is antialiased and is
- easily cut-and-pasted in OS X's native PDF format. Get it <ulink
- url="http://sourceforge.net/projects/aquaterm/files">here</ulink>.
- It can also be installed from either the <ulink
- url="http://fink.thetis.ig42.org/">Fink</ulink> or <ulink
- url="http://www.macports.org/">MacPorts</ulink>
+ "terminal" that is highly recommended. All output is antialiased and is
+ easily cut-and-pasted in OS X's native PDF format. Get it <ulink url="http://sourceforge.net/projects/aquaterm/files">here</ulink>.
+ It can also be installed from either the <ulink url="http://fink.thetis.ig42.org/">Fink</ulink> or <ulink url="http://www.macports.org/">MacPorts</ulink>
projects.</para>
</sect2>
-
<sect2>
<title>X11</title>
-
<para>Apple supplies the X11 windowing system that is popular on some
other Unix and Linux operations systems. Formerly it was available as part
of the Developer Tools but as of OS X 10.8 it is a separate installation.
All PLplot programs made with the Ada bindings will run on X11. In fact,
some types of interactivity such as Example 17 will not run on
- Apple's Terminal.app and should be run on X11 (or
+ Apple's Terminal.app and should be run on X11 (or
some other output device such as TCL/TK).</para>
</sect2>
-
<sect2>
<title>GNAT for OS X</title>
-
- <para>A web site for OS X users is at <ulink
- url="http://www.macada.org/macada/Welcome.html">www.macada.org</ulink>.
+ <para>A web site for OS X users is at <ulink url="http://www.macada.org/macada/Welcome.html">www.macada.org</ulink>.
Although rather dated, the mailing list is still active. Assistance can be
found at other places on the web including the usenet comp.lang.ada.</para>
</sect2>
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