                      Appendix B: Examples
             -----------------------------------

This appendix presents some examples of the DISLIN manual in
DISGCL coding. The examples can be found in the  DISLIN sub-
directory gcldir and can be executed with the command:

disgcl  example 

where example is one of the examples.

B.1 Demonstration of CURVE

%GCL
// Demonstration of CURVE

N=101
PI    = 3.1415926

XRAY  = FALLOC (N)          
XRAY  = (XRAY - 1.) * 3.6
YRAY1 = SIN (XRAY * PI / 180.)
YRAY2 = COS (XRAY * PI / 180.)

METAFL ('CONS')
DISINI ()
COMPLX ()
PAGERA ()

NAME   ('X-axis', 'X') 
NAME   ('Y-axis', 'Y') 
TITLIN ('Demostration of CURVE', 2)
TICKS  (10, 'X')
DIGITS (-1, 'X')

GRAF   (0.,360.,0.,90.,-1.,1.,-1.,0.5)
TITLE  ()

CURVE  (xray, yray1, n)
CURVE  (xray, yray2, n)

DASH   ()
XAXGIT ()
DISFIN ()

B.2 3-D Colour Plot

%GCL
// 3-D Colour Plot
 
N = 100
FLOAT ZMAT[N,N], XRAY[N]

PI = 3.1415927
STEP = 2. * PI / (N - 1)

DO I = 0, N - 1
  XRAY[I] = SIN (I * STEP)
END DO

DO J = 0, N - 1
  ZMAT[*,J] = 2 * XRAY * SIN (J * STEP)
END DO

METAFL ('CONS')
DISINI ()
COMPLX ()
PAGERA ()

DIGITS (-1, 'XYZ')
NAME   ('X-Achse', 'X') 
NAME   ('Y-Achse', 'Y') 
NAME   ('Z-Achse', 'Z') 
TITLIN ('3-D Colour plot of the function', 1)
TITLIN ('F(X,Y) = 2 * SIN(X) * SIN(Y)', 3)

AUTRES (50,50)
GRAF3  (0.,360.,0.,90.,0.,360.,0.,90.,-2.,2.,-2.,1.0)
TITLE  ()

CRVMAT (ZMAT, N, N, 1, 1)
MPAEPL (3)
DISFIN ()

B.3 Surface Plot

%GCL
// Surface Plot
N = 100
FLOAT ZMAT[N,N], XRAY[N]

PI = 3.1415927
STEP = 2. * PI / (N - 1)

DO I = 0, N - 1
  XRAY[I] = SIN (I * STEP)
END DO

DO J = 0, N - 1
  ZMAT[*,J] = 2 * XRAY * SIN (J * STEP)
END DO

METAFL ('CONS')
SETPAG ('DA4P')
DISINI ()
COMPLX ()
PAGERA ()

AXSPOS (200, 2600)
AXSLEN (1800, 1800)

NAME   ('X-axis', 'X') 
NAME   ('Y-axis', 'Y') 
NAME   ('Z-axis', 'Z') 

TITLIN ('Surface plot (SURMAT)', 2)
TITLIN ('F(X,Y) = 2 * SIN(X) * SIN(Y)', 4)

VIEW3D (-5.,-5.,4.,'ABS') 
GRAF3D (0.,360.,0.,90.,0.,360.,0.,90.,-3.,3.,-3.,1.)
HEIGHT (50)
TITLE  ()

COLOR  ('GREEN')
SHLSUR ()
SURMAT (ZMAT, N, N, 1, 1)

DISFIN ()

B.4 Contour Plot

%GCL
// Contour Plot
N = 100
FLOAT ZMAT[N,N], XRAY[N]

FPI = 3.1415927 / 180.
STEP = 360. / (N - 1)
X = FALLOC (N) * STEP
Y = FALLOC (N) * STEP

DO J = 0, N - 1
  ZMAT[*,J] = 2 * SIN (X * FPI) * SIN (Y[J] * FPI)
END DO

METAFL ('CONS')
SETPAG ('DA4P')
DISINI ()
COMPLX ()
PAGERA ()

INTAX  ()
AXSPOS (450, 2670)

NAME   ('X-axis', 'X') 
NAME   ('Y-axis', 'Y') 
TITLIN ('Contour plot', 2)
TITLIN ('F(X,Y) = 2 * SIN(X) * SIN(Y)', 4)

GRAF (0.,360.,0.,90.,0.,360.,0.,90.)

HEIGHT (30)
DO I = 1,9
  ZLEV = -2.0 + (I - 1) * 0.5
   IF (I == 5)
    LABELS ('NONE', 'CONTUR')
   ELSE
    LABELS ('FLOAT', 'CONTUR')
  END IF
  CONTUR (X, N, Y, N, ZMAT, ZLEV) 
END DO

HEIGHT (50)
TITLE  ()
DISFIN ()

B.5 Shaded Contour Plot

%GCL
// Shaded Contour Plot

N = 100
FLOAT ZMAT[N,N], XRAY[N], YRAY[N], ZLEV[12]

STEP = 1.6 / (N - 1)
XRAY = FALLOC (N) * STEP
YRAY = FALLOC (N) * STEP
X    = XRAY * XRAY - 1

DO J = 0, N - 1
  Y=YRAY[J] * YRAY[J] - 1.
  ZMAT[*,J] = X * X + Y * Y
END DO

METAFL ('CONS')
SETPAG ('DA4P')
DISINI ()
COMPLX ()
PAGERA ()

NAME   ('X-axis', 'X') 
NAME   ('Y-axis', 'Y') 

MIXALF ()
TITLIN ('Shaded Contour Plot', 1)
TITLIN ('F(X,Y) = (X[2$ - 1)[2$ + (y[2$ - 1)[2$', 3)

SHDMOD ('POLY', 'CONTUR')
AXSPOS (450, 2670)
GRAF   (0., 1.6, 0., 0.2, 0., 1.6, 0., 0.2)

HEIGHT (30)
DO I = 0, 11
  ZLEV[11-I] = 0.1 + I * 0.1
END DO

CONSHD (XRAY, N, YRAY, N, ZMAT, ZLEV, 12) 

HEIGHT (50)
TITLE  ()
DISFIN ()

B.6 World Coastlines and Lakes

METAFL ('CONS')
DISINI ()
PAGERA ()
COMPLX ()

AXSPOS (400, 1850)
AXSLEN (2400, 1400)

NAME   ('Longitude', 'X')
NAME   ('Latitude', 'X')
TITLIN ('World coastlines and lakes', 3)

LABELS ('MAP', 'XY')
GRAFMP (-180.,180.,-180.,90.,-90.,90.,-90.,30.)

GRIDMP (1, 1)
COLOR  ('GREEN')
WORLD  ()
COLOR  ('FORE')

HEIGHT (50)
TITLE  ()
DISFIN ()

B.7 Widgets

%GCL
// Widgets
 
CL1  = 'Item1|Item2|Item3|Item4|Item5'
CFIL = ' '

SWGTIT ('Example')
IP = WGINI ('VERT')
ID_LAB = WGLAB (IP, 'File Widget: ')
ID_FIL = WGFIL (IP, 'Open File', CFIL, '*.c')

ID_LAB = WGLAB (IP, 'List Widget: ')
ID_LIS = WGLIS (IP, CL1, 1)

ID_LAB = WGLAB (IP, 'Button Widgets')
ID_BT1 = WGBUT (IP, 'This is Button 1', 0)
ID_BT2 = WGBUT (IP, 'This is Button 2', 1)

ID_LAB = WGLAB (IP, 'Scale Widget')
ID_SCL = WGSCL (IP, ' ', 0., 10., 5., 1)

ID_OK  = WGOK  (IP)
WGFIN ()

CFIL = GWGFIL (ID_FIL)
ILIS = GWGLIS (ID_LIS)
IBT1 = GWGBUT (ID_BT1)
IBT2 = GWGBUT (ID_BT2)
XSCL = GWGSCL (ID_SCL)

FREE IP, CL1, ID_LAB, ID_OK, ID_FIL, ID_LIS, ID_BT1 @
     ID_BT2, ID_SCL
LIST
