SPACE 2/SPACE - Library 2 - Volume 1.iso/apps/386/doc/graph.doc

Text File | 1989-05-31 | 16KB | 343 lines

                    GRAPHICS

Graph menu

The REGULAR selection will graph the data with the labels you
have entered in the data entry area along the "X" axis. The
type of graph will depend on the selections you have made in
the "styles" area. Up to 6 variables may be chosen. You may
plot some against the left axis and some against the right
axis.

The HORIZONTAL graph option puts the labels on the "Y" axis
and the values along the "X". You can not have a right side
axis for this type of graph.
"XY" graphs allow up to 6 pairs of variables to be used. You
must select your data a pair at a time. The first one chosen
of each pair will be the "X" value of the point and the
second will be the "Y". You may repeat the same selection
between pairs so that you can have several variables graphed
against the same "X". There are no XY bar graphs. You can
not have a right side axis.

HI LO graphs are stock market graphs. The first 3 variables
chosen will be displayed as a high low close type of graph.
The remainder of the 6 possible graphs will be shown as
selected on the styles section. You can use right side axis
which allows you to graph volume on the same graph as stock
prices. You can have a hi low graph with only 2 variables.
In this case the data represents simply a high and low but
no close.

PIE CHARTS. You may have up to 4 pies on the screen. Simply
specify the correct number of variables. A special case
exists for 2 pie charts if you have selected "component pies"
from the features menu. In this case the second variable will
be assumed to be an explosion of the first pie segment.

BUBBLE GRAPHS require 3 variables to be chosen. The first
specifies the "X" value of the point. The second specifies the
"Y" value of the point and the third specifies the relative
area of the bubble.

OPPOSED  BARS  require 2 variables  which  must  be positive.
If logs are on they are ignored. Opposed bars  are good for
comparing similar  data  against one another.  an example
might be the population of the  U.S.A.   by  age  group
where  one   variable represents  males  and  another
females.  The  key feature of opposed bars is that there is
no  offset between  the  variables.  One  peculiarity  of
the implementation  comes up in rescaling.  The  second
variable  is  treated  as  being  negative  by  the program.
Thus  the  minimum value is  shown  as  a negative.  This is
a requirement so ensure that you enter  a negative for the
minimum,  even though  it will be printed as a positive.

FLOATING  BARS  require 2 variables for each  bar plotted.
The  first represents the minimum of the floating bar and
the second the top. Like XY graphs you will continue to be
prompted for input  until you  fail to enter 2 variables.
This is not an  XY graph however. The X-axis is scaled by
the labels just as for a regular graph.

HORIZONTAL  FLOATING BARS are the same  as  regular floating
bars  except  that  the  graph  is   done horizontally.

POLAR PLOTS are a variation on XY graphs. Selection
procedures are the same. The difference is that the variables
chosen give the angle in radians and distance of the point
rather than "X" and "Y" respectively.

3D BARS allow for up to 18 points in each factor. The data
is displayed with a three  dimensional  aspect. The
variables are displayed behind one another  with the first
variable chosen being the front  variable. In some cases
data points will not be seen since  the column will be
entirely hidden. No right side scaling may be used.

STAT GRAF

These procedures are particular graph types used for analysis.

A STAR GRAPH produces a chart describing the physical values
of several variables at each of several points.
There should be no negative values.
For each point a series of lines are drawn starting at
3 O'clock and then working counterclock wise around the
point. The length of the lines represents how high the value
of the variable is for that point. The minimum value of the
line is set to 20 percent of the maximum.

A SUN RAY GRAPH is similar in concept. In this case each line
is the same length but the line is cut at a value indicating
relative length.If the line is cut exactly in the middle then
the point has a value for that variable which is at the mean
for all points.

A BOX WHISKER GRAPH requires the selection of a variable and
a category variable. The box and whisker are then drawn for
values from the first variable where the categorical variable
is at a certain level. The box and whisker is a regular
style graph. The box has it's top valu at the 3rd quartile
point and its bottom at the first quartile. The box is
bisected by a line at the median. Extending out from the box
at top and bottom are the whiskers. These reach out to the
highest and lowest point in the data variable for a given
level of the categorical variable.

The NOTCHED BOX WHISKER is the same except that there is an
additional piece of information given. There is a notch in
the box which covers a 95 percent confidence limit on the
median. The depth of the notch is proportional to the number
of  elements in  the  variable  with  that  value  of  the
categorical variable.

XYZ graphs are similar to XY graphs.  The main difference is
that there are three coordinate axes,  and you must pick the
variables in threes. Another change is the lack of a legend.
No legend is put on the right of the graph to allow for  the
extra  width  taken  by the  three  dimensional  graph.  For
labelling you will need to use the custom labelling feature.
For XYZ graphs you may select point,  line and bar  options.
The  bar  option  does not actually  produce  bars  in  this
situation.  Instead,  a  perpendicular is dropped to the  XY
plain.  This  gives a better indicator of the height of  the
point.

Z function plots are three dimensional graphs of a  function
of  the  form Z=f(X,Y).  You will be asked  to  specify  the
graphing  limits for X,Y and Z.  You will then be  asked  to
specify the equation and then the number of steps to make in
each  of the X and Y directions.  The greater the number  of
steps,  the  finer the graph but also the slower the  graph.
With 50 steps in each direction there are 5000 calls to  the
parser  and this can be a slow process.  After  setting  the
parameters  you will be asked whether you want hidden  lines
or  not.  The  default  is for no hidden lines  (ie  a  wire
frame).

The next option is a combination of the previous 2. The main
use  for  this  option is to examine actual  points  from  a
regression against the 3D regression surface provided by the
computer.

The  Z Data plot assumes that all of the data in the  editor
represents  Z values for particular combinations of X and  Y
which  are  uniformally spaced.  It does not know  what  the
minimum and maximum X and Y values are. You will be asked to
specify the maximum and minimum for X,Y, and Z just as for a
function  plot.  You will not need to specify the number  of
steps  since  that  is  determined by  the  amount  of  data
available.  As an example consider a select mortality  table
as  used by an insurance company.  There would be  rates  of
mortality  for each issue age and for each of the  first  15
durations since the policy was issued. If we were to examine
mortality rates for ages 15 to 75 and for durations 1 to  15
the  data  would be set up as follows.  There  would  be  15
columns in use.  Each row in the column would represent  the
mortality  level  at a given age for  that  duration.  There
would be 61 rows to handle the various ages.  The number  of
steps would internally be set to 60 and 14 with this data.

For  all  of the XYZ graph types the "right side"  title  is
used to label the "Y" axis.

SETTINGS

The settings menu allows you to define how the graph will
look.

The palette setting allows you to set the palette for the
graph

User  Fill allows you to define up to 6 fill  patterns  for
use by the program. These may be saved and reloaded for the
next use of B/STAT. They are not compatable with fill files
from DEGAS.

Styles allows setting the line style fill pattern and point
style. It also allows you to turn on lines bars or points.
All 3 can be on for any given variable.

Pie Style allows you to set colors and fill styles for pies
as well as whether a slice is exploded.

Background allows for setting a background fill pattern over
which the graph is drawn. There are two types of fill, Full
and Partial. For Full the entire graph area is filled in.
For Partial only the part of the  graph between the axis
lines is filled  in. The selection of fill style is the same
as for pie or bar styles.

Axes allows turning scaling or axes on and off as well as
selecting the color to be used. Tic marks may be turned on or set
to go in or out.

Titles allows you to enter the titles to be used on the graph.

Title Fonts allows you to select the color and style of the
titles and scales used in the graph.

Tic size allows the setting of major and minor tic lengths.
Features

Boxed means that for regular and horizontal graphs a line
will be drawn to close in the graph.
Rt side axis will allow a right side axis on regular graphs.

Stacked will give stacked bar graphs and area graphs for
line graphs.

Filled will cause the area between lines to be filled in.
It can not be combined with stacked.

Vals above will cause the value of the point to be
displayed above it for regular and horizontal graphs.
For Pie charts the values will be printed below the pie label.

Legend will cause the legend for each variable to be
displayed. If turned off then the graph will be larger but
you will have to use custom labelling to define what the
variables are.

Log X causes the X axis to be on a LOG basis.

Log Y does the same for the Y axis.

Proportional Pie means that if more than 1 pie is shown
on the screen at once there relative sizes will be
determined by the total of the values in each pie. This
is quite usefull when comparing 4 years of sales data.

Component Pie. When 2 variables are selected for a pie
graph this option causes the second variable to be taken
as a subset of the first pie sector. The values in the
second variable are displayed as a stacked bar set to the
right of the pie.

Pie  Percent  will cause the  percentage  each  pie slice
represents to be printed in the  pie  slice. The  percent
is rounded to the nearest whole percentage.

Redraw will redraw the graph if the reset graph option is
off.


Grids
These two options turn on horizontal and vertical grids and the
Z grids.
There is also a "zero line" option to ensure that  a line
is drawn at the zero point even if  no grids are displayed.

While  a graph is on screen labels may be added  by double
clicking where you want them to appear.  You will  be
required to select the font and size for the label just
as for titles. You have the  option of adding an arrow.
Simply click where you want it to  point. These labels
may be  dragged on the screen. To remove a floating label,
double click on the label. You are now asked "What to Change?".
This can be either font, text, or arrow. You can remove
the label by selecting text and erasing the existing  text.
A label with no text is simply removed from the list
of labels. If you choose arrow you can either add an
arrow if one does not exist or move the anchor point  for
an existing arrow, or remove the arrow.
You may also resize the graph. This is done by placing
the mouse in the lower right corner of the graph and then
draging the mouse. The graph can be reduced to 1/4 its
original size. You may also reposition the smaller
graph by holding down the mouse button while the mouse is
inside the axes.

The  menu bar displayed while a graph is on screen allows
you to save or print the graph. The "Save" menu items
allow three forms of saving the screen image. The first
is as a DEGAS compatable uncompressed image. The second is
as a ".IMG"  file which can be used by desktop publishing
programs.
With a color system you will be asked if you want  a color
IMG file. Many desk top publishing programs can not handle
a color file so you can put out a monochrome version of
the screen.
The  IMG files produced by BSTAT are compatable  with IMG
files on MSDOS machines. They can therefore be used with
Wordperfect version 5.0 on these  machines. Note that IMG
files are bit image files. The quality of reproduction is
not as good as using a GDOS  print to the same physical
size area.
The third choice is as a metafile. Metafiles can be read  by
programs such as Easy Draw and many desktop  publishing
programs such as Pagestream, Calamus and the Timeworks Desktop
Publisher (TWDTP). To read the files into TWDTP you will need to select
the "GEM DRAW" option in TWDTP.

When printing you have three options. First you can print
the screen using the built in  Atari screen dump utility or
one which you have loaded yourself. The  second option is
usefull only for 9 pin Epson printers. This option uses the
Epson plotter mode to ensure properly scaled pictures. It
also  only works with the monochrome monitor.
The third choice uses GDOS if you have it to plot to the
printer. The text on the graph will not usually look quite
the same as on the screen since many GDOS fonts are
proportional and the default screen fonts are not. Also
some of the printer fonts are not quite the same size as
the screen fonts.
The remaining choices are to adjust GDOS printing.
The GDOS settings item allows you to decide on the width
and height of the graph on the paper. Various GDOS drivers
as well as printers will start graphs in different places.
Thus setting the starting position offset to be zero may not
put the graph at exactly the edge of the paper. Many Epson
clones start graphics 1/4 of an inch from the edge. You should
therefore do a GDOS print of a graph with the standard settings.
Before doing the print turn on "GDOS box". This will result
in a box being drawn around the edges of the graphing area.
You can then use the resulting positions to establish a
vertical and horizontal offset for your particular printer.
The "GDOS Device" Selection allows you to set the device ID
that the program uses to that which you have set in your
ASSIGN.SYS file. Most users will never have to use this
setting. The default in B/STAT is device 21 which  is the
usual standard. This choice is for those lucky individuals
who have more than one printer in use or who have a plotter
which is supported by GDOS.
"GDOS Rotate" allows you to print the graph in landscape mode
as opposed to the normal portrait orientation.

The miscellaneous menu contains only one unusual feature. The
"Keep  Labels" option when chosen (the default) ensures  that
the  custom labels will be kept when you return to the  graph
selection screen. To get rid of them all, simply deselect the
option.
Also on the miscellaneous menu is the selection for "Legend
Box". When this is selected the legend may be dragged around on
the graph until you release the button. If the option has
already been selected then reselecting it will result in
returning to the default setting. When selected you may further
move the legend by selecting "Move Legend".

Reset Graph is normally set. If off then you can redisplay the
graph from the previous menu simply by doing a redraw.