Really Useful CD 1/ReallyUsefulCD1.iso/extras/graphics/_chartdraw/_help

Text File | 1989-10-14 | 7.8 KB | 177 lines

!Chartdraw (v. 1.00)
--------------------

by Chris Johnson.

This fully multi-tasking application allows the production of a range
of charts from data that can be entered and edited. The program plots
line graphs, stacked and grouped barcharts and piegraphs. The current
implementation allows only 2D-representations, although it should be a
not too difficult task to modify the code to give 3D-plotting.

Clicking on the !chartdraw directory installs the application on the
icon bar. Clicking on the icon opens a scrolling edit window into
which the data to be displayed can be entered. Labels to append to the
axes etc. are also entered. Loading in one of the demonstration data
files should show how the edit window operates.

If the program is newly started, or any previous data has been
cleared, then the edit grid will be empty. If the program has been
used previously, any data already entered will be displayed. Text
labels can be entered into the boxes as required. The caret can be
placed anywhere using the mouse. Pressing return will automatically
move the caret into the next box of the edit window (the caret need
not be at the right hand end of the text) with automatic scrolling as
necessary. All editing is carried out in the standard fashion of the
RISC OS WIMP environment. When editing, it is NOT necessary to press
<RETURN> for the changes to be implemented (some applications require
<RETURN> to be pressed before changes are actually made).

      WARNING: All the editing is carried out on strings of
      characters. These strings are converted to numerical values
      when the charts are drawn. The application does not check
      these strings for non-numerical content before it converts
      using the VAL function. It is up to the user to check the
      data entered for mis-typing etc.


Clicking the menu button on the edit window will allow six choices.

Clear
-----
      This will clear the data (screen display and memory
      buffer) ready to begin entering the data for a new
      chart (NB. Once its gone its gone!!!).

Save
----
      This acts in the standard RISC OS way. You can enter a file name
      and drag the save icon to an open directory viewer, or if the
      full path name is set up (eg. the data was loaded from disk)
      then it is necessary only to click on OK. When data is saved to
      disk it is given a user defined filetype so that the application
      is able to recognise datafiles to load back in. The filetype
      number is easily changed if it clashes with any other
      application filetypes.

Piechart/Linegraph/Bargraphs
-----------------------------
      These options cause the plotting of the chosen type of chart. In
      the case of the piechart, a dialogue is first initiated to
      choose between plotting a single large pie, or up to four small
      ones.


Chart window menus
==================

Once a chart has been drawn, clicking on its window with the menu
button will present a number of choices. Some of these are common to
all charts, others are more specific. All the actions are summarised
below.

Some actions are fairly clear. It is possible to replot the chart in
another form by choosing the new chart. If pie is chosen, then the
dialogue box described above is first opened. For charts that use
fills, then it is possible to toggle between solid fills and hatched
patterns. The replotting is always impressive in its speed, although
everything is in BASIC, with long variable names etc. The barcharts
can be toggled between vertical and horizontal bars as the user
wishes.

When the charts are plotted the program selects automatically the
range of the axes and the size of the index marks along the axis. For
barcharts, it is assumed that the origin (zero) should be included in
the graph, whereas the linegraph is plotted over the range of values.
The program chooses round numbers for the range and indexing along the
axes (eg. a full scale of 2000 rather than 1922.5, with indexing at
400, rather than 384.5?). The change axes option allows the user to
override to some extent the program choice, although the algorithm is
not completely overriden, in that round numbers close to the user
entered values may be chosen rather than the exact values entered!
Piecharts always add up to 100%, so there is no need for any user
choice.

The labels option is one way in which extra annotation can be added to
the charts. The sub-menu allows the user to add a label or clear ALL
labels for that particular chart. Choosing add will cause the menu to
disappear. It is then necessary to click (with SELECT) on the chart at
the position the label is to be added. A dialogue box will open
allowing the label text to be entered, and the choice made whether the
text is to the left of, centred on or to the right of the chosen
position. It is also possible to choose vertical, when the text will
run DOWN from the index position (eg. to label a y-axis). Pressing
<RETURN> will clear the dialogue box and put the label in position.
The program will accept up to twelve labels for each type of chart.
The position and content of a label is remembered even if the graph
window is closed and the data then replotted, or if a different style
of chart is plotted. The current version of the software does not
allow labels, once entered, to be edited, other than to delete them
and start again (well it is cheap software!). The labels are saved and
loaded along with the data, assuming you save the data AFTER they have
been defined.

In the piechart menu, choosing segments allows one or all segments to
be `exploded' or returned to normal. If the selection is for one
segment, then when the menu clears, clicking SELECT on a particular
segment will explode (or return) that segment. If there is more than
one piechart on screen, then the corresponding segment in each pie
will be exploded or returned. More than one segment can be exploded by
choosing one segment from the menu as many times as necessary, and
clicking on a different segment each time.

Save Screen - in this version selecting this option will cause the
whole chart screen to be saved as a screen sprite. The filename is
grafwinX, where X starts at 1 and increments each time a screen is
saved. The value of X is reset to 1 when the program is QUIT and
restarted. Old screen files will then be overwritten.

The grafwin file subsequently may be loaded into !paint or !edit for
further editing or may be dragged to the !printerDM or !printerPS
icons on the iconbar for hardcopy.

Loading of data files
---------------------

The application can be started up by simply double clicking on a data
file of the correct type. A window is opened and the data is displayed
within the keystrip grid, ready for editing or printing. Data can also
be loaded in all the other WIMP ways, i.e. drag the file into an
already open window or drag the file to the application icon on the
iconbar. The application will ignore any file that is not of the
correct type.

Example data files
------------------

A number of !chartdraw data files are on the disk in the directory
CHARTDATA. Any of these can be loaded in for demonstration purposes.




If you have any comments on this program, or would like to suggest
ways in which it could be improved then the author can be contacted
directly.

Chris Johnson
7 Lovedale Grove
Balerno
Edinburgh
EH14 7DR

If you wish to enter into the `shareware' concept in the full sense
then contributions, however small, will be gratefully received by the
author. Registration would, of course, entitle the user to free
upgrades of the software (send a blank disk).

If, in any communication, you make specific reference to the program
code, then please (a) quote the version number (b) refer only to the
program as issued and (c) do not renumber it. Please send an SAE if
you require a reply.

I hope you find the program of some use.

CJ 12/10/1989