1.4. Tutorial example 2

Next example includes every important elements for minimum usage of ANGEL . If you have no time to have a read the following manual through, it is enough to learn this example for starting ANGEL . We show an input file and output graph in the following.

List 1.2 • Input of tutorial example 2

 1:  'Figure 2'                                          --- (1)
 2:  X: E (MeV)                                          --- (2)
 3:  Y: d\sigma/d\OmegadE (nb/MeV/sr)                    --- (3)
 4:  W:Comment = ^{12}C + ^{40}Ca/ X(1) Y(65)             --- (4)
 5:  A: X(4.3) Y(65) AX(5.5) AY(53)                      --- (5)
 6:  AW:Arrow/ X(4.5) Y(23) AX(4) AY(10)                 --- (6)
 7:  H:  X   Y(Histogram),DH0                            --- (7)
 8:      0.0    0
 9:      0.5   10
10:      1.5   20
11:      2.5   35
12:      3.5   30
13:      4.5   45
14:      5.5   70
15:      6.5    0
16:  H: X  Y(Spline),SL5                                 --- (8)
17:    0.5   40
18:    4     10
19:    6     20
20:    7     60
21:  H: X   DX    Y(Error bar),N3    D                   --- (9)
22:     2    1         50           10
../_images/fig102.png

Fig. 1.2 Tutorial example 2

You can see a high quality image produced from a simple input by ANGEL . First, let me explain the points denoted by number in right-hand side of input lines in List 1.2.

  1. Title of graph '   '
    The title of graph is specified between '   '. This is shown in the middle upside the graph frame. The title can be removed and moved to horizontal direction by the parameter.
  2. Title of X axis X:
    The title of X axis is defined by the line started from X:. You can use italic, bold, special characters, and other various expression of the characters in the title and also in any line of string.
  3. Title of Y axis Y:
    The title of Y axis is defned by the line started from Y:.
  4. Comment W:
    The comment in the figure is defined by the line started from W:. The strings from W: to / are shown in the figure at the point specified by X(  ) Y(  ) as a comment.
  5. Arrow A:
    The arrow in the figure is defined by the line started from A:. The start and end points of the arrow are specified by X(  ) Y(  ) and AX(  ) AY(  ), respectively.
  6. Arrow with Comment AW:
    This is a combination of arrow and comment. The strings from AW: to / are shown in the figure at the point specified by X(  ) Y(  ) and the arrow is described to AX(  ) AY(  ).

In the following sections, we will explain another parameters which define the more detail of the above objects.

Next, we explain the basic section in ANGEL , H:, which defines the x-y graph. There are three H: sections (7), (8) and (9) in this example. The main purpose of this line of H: is to define the ordering of the following columns. As shown in the previous example, if the numerical data consist of x-value and y-value columns, we should write H: X  Y. By this line, we can additionally define line type, symbol type, color, and legend.

The strings in the parenthesis after Y like Y(Histogram),DH0 are automatically shown in the right hand side of the graph frame as legends. The strings after the comma define the line type (D = Dashed Line, L = Solid Line, N = No Line), spline (S = Spline), histogram (H = Histogram), and symbol type (0 = No Symbol, 3 = Open Circle).

In the last section of (9), there are columns defined by DX, D. These define the error bars. DX defines the error bar of the X column, D defines the error bar of the Y column just before. In default, the value of the error is the same values around the y-value. It is explicitly expressed by D+-. If you want to define the different error values upper and lower values around the y-value, you should define those by different columns like D+  D-.

In ANGEL , we call ’section’ the part of the input file starting from alphabet characters with colon : like AW: H:.