# axes properties

description of the axes entity properties

## Description

The Axes entity is the second level of the graphics entities hierarchy. This entity defines the parameters allowing the change of coordinates and the axes drawing as well as the parameters' default values for the children creation.

Axes properties
  parent:

    This field contains the handle of the parent figure.

  children:

    FA vector containing the handles of all graphics objects children of the axes These graphics objects are of type `"Compound"`, `"Rectangle"`, `"Polyline"`, `"Segs"`, `"Arc"`, `"Grayplot"`,.. (see Compound_properties, rectangle_properties, champ_properties, axis_properties, polyline_properties, segs_properties, grayplot_properties, surface_properties, fec_properties, text_properties, legend_properties)

  visible:

    This field contains the `visible` property value for axes . Its value should be `"on"` or `"off"` . By default, axes is visible `"on"` in case all "visible" chidren are displayed on the screen, If `"off"` the axes and all its chidren are not drawn.

  axes_visible:

    A `1x3` string vector. This property specifies whether each axis is drawn or not. Its value should be `"on"` or `"off"` for a global setting.To act on a single axis, the syntax is `axes_visible(N)` where `N` is `1,2` or `3` corresponding to the `x,y` or `z` axis. The scaling data and if required the grids are drawn if the value is `"on"`. Note that when creating a simple axes entity using the `gca()` (shorcut for `get"current_axes")`) or `gcf()` (shortcut for `get(current_figure)`) commands, the axes visiblibilty is set to `"off"`.

  axes_reverse:

    A `1x3` string vector corresponding to the three axes (X,Y,Z). For each axes, the property specifies the direction of the incresing values. If `"off"`, the default direction is used. If `"on"`, the direction is reverse. It is also possible to use only one string, `"on"` or `"off"`, to set simultaneously the three data.

  grid:

    The field value is a vector `[x-grid,y-grid,z-grid]` where `x-grid` controls a grid drawning for the x-axis and `y-grid, z-grid` respecting to the y-axis, z-axis. The default values is `-1` grids are not drawn, else the grids are drawn using the color given indexed by the grid value.

  grid_position:

    This character string specifies the grid position compared with other graphic entities. Its value can be either `"foreground"` to draw the grid ahead other graphic entities or `"background"` to draw the grid behind.

  x_location:

    Specify the location of the x-axis. The possible values are:

    - `"bottom"`. In this case the x axis is drawn at the bottom of the axes rectangle.

    - `"top"`. In this case the x axis is drawn at the top of the axes rectangle.

    - `"middle"`. In this case the x axis is drawn at the centered position.

    - `"origin"`. In this case the x axis is drawn at the origin.

  y_location:

    Specify the location of the y-axis. The possible values are:

    - `"left"`. In this case the y axis is drawn at the left of the axes rectangle.

    - `"right"`. In this case the y axis is drawn at the right of the axes rectangle.

    - `"middle"`. In this case the y axis is drawn at the centered position.

    - `"origin"`. In this case the y axis is drawn at the origin.

  title:

    An object attached to the Axes entity and returning a graphic handle on a Label structure (see label_properties). This field defines a title with options on this label.

  x_label:

    An object attached to the Axes entity and returning a graphic handle on a Label structure (see label_properties). This field defines a label on x axis with options on this label.

  y_label:

    An object attached to the Axes entity and returning a graphic handle on a Label structure (see label_properties). This field defines a label on y axis with options on this label.

  z_label:

    An object attached to the Axes entity and returning a graphic handle on a Label structure (see label_properties). This field defines a label on z axis with options on this label.

  auto_ticks:

    A `1x3` string vector giving the auto_ticks status for each axis. This property specifies whether each axis is graduated using a computational algorithm or not (graduations are set by the user). Its value should be `"on"` or `"off"` for a global setting.To act on a single axis, the syntax is `auto_ticks(N)` where `N` is `1,2` or `3` corresponding to the `x,y` or `z` axis. Note that editing ticks (text and/or locations) via `x_ticks, y_ticks` or `z_ticks` automatically set `auto_ticks` to `"off"` for the corresponding axes.

  x_ticks, y_ticks, z_ticks:

    Each of these properties is a tlist of type "ticks" with 2 fields named "locations" and "labels": `tlist(["ticks", "locations", "labels"], Locations, Labels)` where

    Locations
      is a real vector containing the locations of graduations along and according to the data scale of the given x or y or z axis. When the number of ticks does not need to be changed, their locations can be set or changed through the syntax (e.g. along x) `Haxes.x_ticks.locations = Locations` where `Haxes = gca();` and `Locations` is the complete vector of updated ticks positions. To change just the ith location, just use: `Haxes.x_ticks.locations(i) = newLoc`
    Labels
      is a text vector containing the labels to be displayed in front of each related graduation. As for Locations of ticks, Labels can be addressed with (e.g. along y) `Haxes.y_ticks.labels = Labels` or `Haxes.y_ticks.labels(j) = newLabelJ`

    For an axis, `Locations` and `Labels` vectors must have the same number of components.

    When the number of ticks must be changed, their positions AND labels must be changed at once, in order to avoid any mismatch: The syntax (e.g. along x) `Haxes.x_ticks = tlist(["ticks" "locations", "labels"], newLocations, newLabels)` must then be used.

  x_ticks.locations, y_ticks.locations, z_ticks.locations:

    Each of these properties is a real vector containing the locations of graduations on the related x or y or z axis. `x_ticks.locations` must have the same number of components as `x_ticks.labels`. See `x_ticks` hereabove for more details.

  x_ticks.labels, y_ticks.labels, z_ticks.labels:

    Each of these properties is a text vector containing the labels to be displayed in front of ticks on the related x or y or z axis. `x_ticks.labels` must have the same number of components as `x_ticks.locations`. See `x_ticks` hereabove for more details.

  ticks_format:

    This property specifies the format to use for each axes. It is a row vector with at most 3 columns containing strings format (as specified for mprintf). Each ticks position will be used to format the string used as label.

    So, for example ticks_format="%.2e" will print ticks positions in using scientific notation with two decimals.

  ticks_st:

    This property specifies scale-translate factors to apply to each ticks position before to use it in the formatted string used as label. So if the factors are `[x_s y_s z_s ; x_t y_t z_t]` and if a x_tick is positionned at X, the value used to format the label will be `x_s*(X-x_t)`. It could be particulary useful when the axes bounds are too closed.

    It is a matrix with 2 rows and at most 3 columns.

    So, for example `base=B`, labels could be printed with `ticks_format=string(base)+"%+.2e"` and `ticks_st=[1 base]`

  box:

    This property specifies whether to enclose the axes in a box. Its value can be either `"off"`, `"hidden_axes"`, `"back_half"` or `"on".` If the property is `"off"`, the box is not draw. If the property is `"hidden_axes"`, only the back frame is drawn. If the property is `"back_half"`, the X, Y and Z axis are also drawn. If the property is `"on"` the whole box is drawn.

  filled:

    This property specifies whether the axes background should be drawn or not. Its value can be either `"off"` or `"on".` If the property is `"off"`, the background is not drawn, the axes box is transparent. If the property is `"on"` the background is drawn using the color specified by the `background` property.

  sub_ticks:

    This field sets the number of tics to draw between two main tics. The field value is the vector `[nx,ny]` where `nx` is the number of sub tics for the x-axis and `ny` respecting to the y-axis.

  font_style:

    Specifies the font used for displaying tics labels. This is a positive integer referecing one of the loaded fonts. Its value must be between 0, referecing the first font, and the number of loaded fonts minus one, referencing the last font. For more information see graphics_fonts.

  font_size:

    It is a scalar specifying the character size of tics labels. If `fractional_font` property is `"off"` only the integer part of the value is used. For more information see graphics_fonts.

  font_color:

    This property determines the color of the tics labels.

  fractional_font:

    This property specify whether ticks labels are displayed using fractional font sizes. Its value must be either `"on"` or `"off"`. If `"on"` the floating point value of `font_size` is used for display and the font is anti-aliased. If `"off"` only the integer part is used and the font is not smoothed.

  isoview:

    This property is used to have isometric scales on the x, y and z axes (for exemple to make the display of the curve sin(x) versus cos(x) be a circle not an ellipse). Its value should be `"on"` or `"off"`. If the value is `"on"`, the axes `data_bounds` automatically change according to the corresponding figure `figure_size` property values.

  cube_scaling:

    This property is used in `3d mode` to have a rescaling of the x, y and z axes. Indeed, it allows the `data` to fit into a 1x1x1 cube ; the goal is to better display 3d graphics in case axes scales are very different from one to another. Its value should be `"on"` or `"off"` (which is the default value). In most cases, it helps generating Matlab-like 3d view.

  view:

    This field is related to the graphics universe. It takes `"3d"` as value corresponding to the three-dimensional views. In the other case its value can be `"2d"` for initial 2d plotting (default value). This flag also depends on the plots the user enters : a `plot3d` command, for example, will switch the `view` flag from `"2d"` to `"3d"`.

  rotation_angles:

    This field is the vector `[alpha,theta]`. These two values give the spherical coordinates of the observation points (in degree).

  log_flags:

    3 character string that sets the scale (linear or logarithmic) along the axes. Each character speficfies the scale for respectivgly the X, Y and Z axes. They should take a value between `'n'` for linear scale or `'l'` for logarithmic scale.

  tight_limits:

    If this property value is `"on"` axes adapt to fit exactly with the minima and maxima values of the data bounds. If this field value is `"off"`, axes may enlarge boundaries such as to produce pretty tics labels.

  data_bounds:

    This field contains the boundary values for the x, y and z coordinates. It is either the matrix or the vector `[xmin,ymin; xmax,ymax]`, `[xmin,ymin,zmin; xmax,ymax,zmax]`, `[xmin,xmax,ymin,ymax]`, `[xmin,xmax,ymin,ymax,zmin,zmax]`, `[xmin;xmax;ymin;ymax]` or `[xmin;xmax;ymin;ymax;zmin;zmax]`. Note that, to stricly have the specified data bounds, `tight_limits` must be set to `"on"` value (see above). To manually set data_bounds set `auto_scale="off"`

  zoom_box:

    This field contains the current zoom box if any coordinates are given. It is an empty matrix (no zoom) or the vector `[xmin,ymin,xmax,ymax,zmin,zmax]` (defines a smaller axes box).

  margins:

    A vector `[margin_left,margin_right,margin_top,margin_bottom]` specifying the margins portion for this axes. This vector is composed of numbers between [0 1] with default: [0.125 0.125 0.125 0.125]. These numbers are ratios relative to associated values of the `axes_bounds` property, which are `width` for `margin_left` and `margin_right`, and `height` for `margin_top` and `margin_bottom`.

  auto_margins:

    A property to allow the automatic computation of the margins accordint to their contents. If value is `"on"`, then the automatic computation is activated.

  axes_bounds:

    A vector `[x_left,y_up,width,height]` specifying the portion of figure used by this axes. Where `x_left`, `y_up`, `width` and `height` are numbers in [0 1] give respectively the position of the upper-left corner and the dimension of the axes (these numbers are ratio relative to the corresponding figure `figure_size` property values).

  hidden_axis_color:

    This property defined the color of the hidden axis. It takes an index relative to the current colormap.

  user_data:

    This field can be use to store any scilab variable in the axes data structure, and to retreive it.

Properties for high level functions

  The `plot`, `plot2dx`, `grayplot` and `matplot` functions use the following properties to decide how to merge consecutive plots if this is not stated by the `frameflag` calling argument. The result of the merge is decided through these two following properties:

  auto_clear:

    If this property value is equal to `"on"`, a call to a high level graphic will re-ininitialize the current axes and erase all its children before preforming the drawing (log_flags will be reset). If the value is `"off"` the drawings will be added to current axes according to `"auto_scale"` property.

  auto_scale:

    A property to update the axes data boundary. If value is `"on"`, a new plot will adapt the current axes properties to fit with previous and current plots. If its value is `"off"` the new plot will be drawn in the current axes data boundary.

Children's default values:
  hiddencolor:

    This property controls the hidden parts' color. It takes as value an index relative to the current colormap. In another case, if it is a negative value, the hidden parts take the same colors as the surface

  line_mode:

    This field contains the default `line_mode` property value for Segs Rectangle Legend Axis Plot3d Fac3d and Polyline objects. Its value should be `"on"` (default) or `"off"`.

  line_style:

    This field contains the default `line_style` property value for Segs, Arcs, Rectangle and Polyline objects. `line_style` selects the type of line to be used to draw lines . Its value should be an integer in [1 10]. 1 stand for solid, the other values stand for a selection of dashes (dash, dash dot, longdash dot, bigdash dot, bigdash longdash, dot, double dot, longblank dot, bigblank dot).

  thickness:

    This field contains the default `thickness` property value for all objects using line drawing. It is a positive real specifying the line width in pixels. The displayed width is actually determined by rounding the supplied width to the nearest integer. The only exception is vectorial export where the whole `thickness` value is considered.

  mark_mode:

    This field contains the default `mark_mode` property value for Segs Rectangle Legend Axis Plot3d Fac3d and Polyline objects. Its value should be `"on"` or `"off"` (default).

  mark_style:

    This field contains the default `mark_style` property value for Segs Rectangle Legend Axis Plot3d Fac3d and Polyline objects. `mark_style` selects the type of mark to be displayed. Its value should be an integer in [0 9] which stands for: dot, plus, cross, star, filled diamond, diamond, triangle up, triangle down, trefle and circle.

  mark_size_unit:

    This field contains the default `mark_size_unit` property value for Segs Rectangle Legend Axis Plot3d Fac3d and Polyline objects. If `mark_size_unit` is set to `"point"`, then the `mark_size` value is directly given in points. When `mark_size_unit` is set to `"tabulated"`, `mark_size` is computed relative to the font size array: therefore, its value should be an integer in [0 5] whith stands for 8pt, 10pt, 12pt, 14pt, 18pt and 24pt. Note that plot2d and pure scilab functions use `tabulated` mode as default ; when using plot function, the `point` mode is automatically enabled.

  mark_size:

    This field contains the default `mark_size` property value for Segs Rectangle Legend Axis Plot3d Fac3d and Polyline objects. `mark_size` selects the font size of mark to be displayed. Its value should be an integer in [0 5] whith stands for 8pt, 10pt, 12pt, 14pt, 18pt and 24pt.

    In the special case where mark_style and mark_size are 0, a dot of one pixel is drawn.

  mark_foreground:

    This field contains the default `mark_foreground` property value for all objects created under this axes. Polyline, rectangle, legend, surface, segment and axis objects are using this property to specify a foreground (edge) color for their marks. Its value should be a color index (relative to the current color_map) or 0 for transparant edge. Note that the default value is `-1` (default black) and, even if you change the `color_map`, this `-1` value will always point onto the default black color.

  mark_background:

    This property controls the default `mark_background` property value for all objects created under this axes. Polyline, rectangle, legend, surface, segment and axis objects are using this property to specify a background (face) color for their marks. It takes as value an index relative to the current colormap or 0 for transparant face. Note that the default value is `-2` (default white) and, even if you change the `color_map`, this `-2` value will always point onto the default white color.

  foreground:

    This field contains the default `foreground` property value for axes and all objects created under this axes. Its value should be a color index (relative to the current color_map). Note that the default value is `-1` (default black) and, even if you change the `color_map`, this `-1` value will always point onto the default black color.

  background:

    This property controls the default `background` property value for axes and all objects created under this axes. It takes as value an index relative to the current colormap.Note that the default value is `-2` (default white) and, even if you change the `color_map`, this `-2` value will always point onto the default white color.

  arc_drawing_mode:

    This property controls the default `arc_drawing_mode` property value for all created Arc objects under this Axes object. Its value should be either `"nurbs"` or `"lines"`.

  clip_state:

    This field contains the default `clip_state` property value for all objects. Its value should be :

    - `"off"` this means that all objects created after that are not clipped (default value).

    - `"clipgrf"` this means that all objects created after that are clipped outside the Axes boundaries.

    - `"on"` this means that all objects created after that are clipped outside the rectangle given by property clip_box.

  clip_box:

    This field contains the default `clip_box` property value for all objects. Its value should be an empty matrix if clip_state is `"off"`. Other case the clipping is given by the vector `[x,y,w,h]` (upper-left point width height).

  Note on default values :

      All these listed properties and fields inherit from default values stored in an axes model. These default values can be seen and changed. To do so, use the `get("default_axes")` command : it returns a graphic handle on the axes model. Note that no graphic window is created by this command. The next created axes will inherit from this model (see "Example on axes model" below).

## Examples

    lines(0) // disables vertical paging
    a=get("current_axes")//get the handle of the newly created axes
    a.axes_visible="on"; // makes the axes visible
    a.font_size=3; //set the tics label font size
    a.x_location="top"; //set the x axis position
    a.data_bounds=[-100,-2,-1;100,2,1]; //set the boundary values for the x, y and z coordinates.
    a.sub_tics=[5,0];
    a.labels_font_color=5;
    a.grid=[2,2];
    a.box="off";

    // Example with 3D axes
    clf(); //clear the graphics window
    x=0.1:0.1:2*%pi;plot2d(x-.3,sin(x)*7+.2);
    a=gca(); // get the handle of the current axes
    a.grid=[1 -1 -1]; //make x-grid
    a.rotation_angles=[70 250]; //turn the axes with giving angles
    a.grid=[1 6 -1]; //make y-grid
    a.view="2d"; //return te the 2d view
    a.box="back_half";
    a.labels_font_color=5;
    a.children.children.thickness=4;
    a.children.children.polyline_style=3;
    a.view="3d"; //return te the 3d view
    a.children.children.thickness=1;
    a.children.children.foreground=2;
    a.grid=[1 6 3]; //make z-grid
    a.parent.background=4;
    a.background=7;
    plot2d(cos(x)+1,3*sin(x)-3);
    plot2d(cos(x)+7,3*sin(x)+3);
    a.children(2).children.polyline_style=2;
    a.children(1).children.polyline_style=4;
    a.children(1).children.foreground=5;
    a.children(2).children.foreground=14;
    a.parent.figure_size= [1200,800];
    a.box="on";
    a.labels_font_size=4;
    a.parent.background=8;
    a.parent.figure_size= [400,200];
    a.rotation_angles=[0 260];
    delete(a.children(2));
    delete(); // delete current object

    a = gca();
    a.labels_font_size=1;
    a.auto_clear= "on";
    x=0:0.1:2.5*%pi;plot2d(10*cos(x),sin(x));

    a.data_bounds(:,1) = [1;15] ; // set positive bounds for X axe
    a.log_flags = "lnn" ; // set X axes to logarithmic scale
    a.log_flags = "nnn" ; // switch back to linear scale

    a=gca();
    a.rotation_angles=[45 45];
    a.data_bounds=[-20,-3,-2;20 3 ,2];
    xrect([-4 0.5 8 1]);
    a.auto_clear = "off" ;
    a.isoview="on"; // isoview mode
    xrect([-2 0.25 4 0.5]);
    a.children(1).fill_mode="on";
    a.axes_visible="off";
    a.children(1).data=[-2 0.25 -1 4 0.5];
    a.children(2).data=[-4 0.5 1 8 1];
    x=2*%pi*(0:7)/8;
    xv=[.2*sin(x);.9*sin(x)];yv=[.2*cos(x);.9*cos(x)];
    xsegs(10*xv,yv,1:8)
    s=a.children(1);
    s.arrow_size=1;
    s.segs_color=5;
    a.data_bounds //the boundary values for the x,y and z coordinates
    a.view="2d";
    a.data_bounds=[-10,-1; 10,1]; // set the boundary values for the two-dimensional views

    // Example on axes model
    da=gda() // get the handle on axes model to view and edit the fields
    // title by default
    da.title.text="My Default@Title"
    da.title.foreground = 12;
    da.title.font_size = 4;
    // x labels default
    da.x_label.text="x";
    da.x_label.text="x"; // Latex or MathML can be used here also
    da.x_label.font_style = 8;
    da.x_label.font_size = 2;
    da.x_label.foreground = 5;
    da.x_location = "middle";
    // y labels default
    da.y_label.text="y";
    da.y_label.font_style = 3;
    da.y_label.font_size = 5;
    da.y_label.foreground = 3;
    da.y_location = "right";
    da.thickness = 2;
    da.foreground = 7;
    // the plot
    x=(0:0.1:2*%pi)';
    plot2d(x,[sin(x),sin(2*x),sin(3*x)],style=[1,2,3],rect=[0,-2,2*%pi,2]);
    sda() // back to default axes model

    // Example with LaTeX / MathML ticks:
    plot2d();
    a=gca();

    mathml="<mrow><mfrac><mrow><mi>d</mi>  <mi>y</mi></mrow><mrow>  <mi>d</mi>  <mi>x</mi></mrow></mfrac> <mo>=</mo>..
    <mfrac><mn>1</mn><msup> <mi>y</mi>  <mn>2</mn></msup> </mfrac> </mrow>";
    // Only LaTeX expression
    a.x_ticks = tlist(["ticks", "locations", "labels"], (0:6)', [mathml;"1";"$\sin(x)$";"3";"$\cos(a) - test$";"5";"6"]);

    // Mixed expression: MathML and LaTex
    a.y_ticks = tlist(["ticks", "locations", "labels"], (-2:0.5:2)', ["0";"1";"2";"3";"$\cos(a)$";"5";"6";mathml;"8"]);

    m=[66.425514; 66.425513];
    plot([69;70], m);
    a=gca();
    a.ticks_format=["" sprintf("%.2f", m(2))+"%+.1e"];
    a.ticks_st=[1 1;0 m(2)];

## See Also

- axis_properties
- lines
- set
- get
- gca
- gda
- gcf
- sda
- sdf
- scf
- graphics_entities

## History

5.4.0
line_style value 0 is obsolete, use 1 instead (both are equivalent for SOLID). Using value 0 will produce an error in Scilab 5.4.1.
5.5.0

- line_style values 9 and 10 can be used to have respectively longblank dot and bigblank dot styles.
- auto_margins property added to allow automatic computation of the margins.
- ticks_format and ticks_st properties added to improve ticks labels display.