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-- $Id: xthick04a.adb.cmake 9378 2009-01-23 09:13:27Z jbauck $
--
-- Log plot demo.
-- Copyright (C) 2007 Jerry Bauck
-- This file is part of PLplot.
-- PLplot is free software; you can redistribute it and/or modify
-- it under the terms of the GNU General Library Public License as published
-- by the Free Software Foundation; either version 2 of the License, or
-- (at your option) any later version.
-- PLplot is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-- GNU Library General Public License for more details.
-- You should have received a copy of the GNU Library General Public License
-- along with PLplot; if not, write to the Free Software
-- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
with
Ada.Numerics,
Ada.Numerics.Long_Elementary_Functions,
PLplot_Auxiliary,
PLplot;
use
Ada.Numerics,
Ada.Numerics.Long_Elementary_Functions,
PLplot_Auxiliary,
PLplot;
@Ada_Is_2007_With_and_Use_Numerics@
procedure xthick04a is
procedure plot1(Plot_Type : Integer) is
freql, ampl, phase : Real_Vector(0 .. 100);
f0, freq : Long_Float;
begin
Advance_To_Subpage(Next_Subpage);
f0 := 1.0;
for i in freql'range loop
freql(i) := -2.0 + Long_Float(i) / 20.0;
freq := 10.0 ** freql(i);
ampl(i) := 20.0 * log(1.0 / sqrt(1.0 + (freq / f0) ** 2.0), 10.0);
phase(i) := -(180.0 / pi) * arctan(freq / f0);
end loop;
Set_Viewport_Normalized(0.15, 0.85, 0.1, 0.9);
Set_Viewport_World(-2.0, 3.0, -80.0, 0.0);
-- Try different axis and labelling styles.
Set_Pen_Color(Red);
if Plot_Type = 0 then
Box_Around_Viewport("bclnst", 0.0, 0, "bnstv", 0.0, 0);
elsif Plot_Type = 1 then
Box_Around_Viewport("bcfghlnst", 0.0, 0, "bcghnstv", 0.0, 0);
end if;
-- Plot ampl vs freq
Set_Pen_Color(Yellow);
Draw_Curve(freql, ampl);
Set_Pen_Color(Red);
Write_Text_World(1.6, -30.0, 1.0, -20.0, 0.5, "-20 dB/decade");
-- Put labels on
Set_Pen_Color(Red);
Write_Text_Viewport("b", 3.2, 0.5, 0.5, "Frequency");
Write_Text_Viewport("t", 2.0, 0.5, 0.5, "Single Pole Low-Pass Filter");
Set_Pen_Color(Yellow);
Write_Text_Viewport("l", 5.0, 0.5, 0.5, "Amplitude (dB)");
-- For the gridless case, put phase vs freq on same plot
if Plot_Type = 0 then
Set_Pen_Color(Red);
Set_Viewport_World(-2.0, 3.0, -100.0, 0.0);
Box_Around_Viewport("", 0.0, 0, "cmstv", 30.0, 3);
Set_Pen_Color(Green);
Draw_Curve(freql, phase);
Set_Pen_Color(Green);
Write_Text_Viewport("r", 5.0, 0.5, 0.5, "Phase shift (degrees)");
end if;
end plot1;
begin
-- Parse and process command line arguments
Parse_Command_Line_Arguments(Parse_Full);
-- Initialize plplot
Initialize_PLplot;
Set_Font_Style(Roman_Font);
-- Make log plots using two different styles.
plot1(0);
plot1(1);
End_PLplot;
end xthick04a;
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