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I
m a g
i n e
I T T
o o l
b a r
Quick
start guide
A new 'Add-in' for Microsoft Excel which provides
an Interactive Modelling And Graphical Information Environment for
IT.
It adds an extra toolbar which enables you to:
Why is it called ImagineIT?
ImagineIT stands for Interactive Modelling And Graphical
INformation Environment for IT.
It aims to make situations easy to imagine,
whether they are described by tables of numerical data that can
be explored using appropriate graphs, or whether they are described
by models involving formulae that describe the relationships between
quantitities.
Quick format buttons
The following simple buttons on the toolbar make
editing spreadsheets a little easier:
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 Paste
formulae
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 Zoom
in/out
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 Calculate now
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 Paste values
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  Show formulae/values
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 Start calculation
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 Paste formats
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 Unprotect/protect
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 Stop calculation
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Shortening the toolbar to leave only formatting
buttons
If you just want to switch the ImagineIT Toolbar
off except for the formatting options, click this button  .
(The graph buttons described below then just change the format of
an existing graph and cannot be used to create new graphs.) To switch
the full toolbar on again click the same button. The shortened toolbar
looks like this:
How to explore data using graphs
Setting up a table of data
-
First you must tell ImagineIT
where your table of data is. (Data must be arranged in
columns, not rows.)
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Select the whole table, excluding column
headings. (Hint: you can drag across the table with the mouse
to select it, or you can click in the top left hand cell, then
hold down shift while you click in the bottom right hand cell.)
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Click 
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Next identify the rows
that you want to use for graph titles, axis labels,
'series labels' (labels that distinguish individual
plots on one graph) and column names (you can use these
in formulae)
Here is a simple example:
Creating a new graph
Choose the two columns that you want to plot one
against the other and the type of graph you want to use:
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Click on any cell in the column that you want
for the y-value (or dependent variable) axis
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Click the appropriate graph button  ,  ,  ,  ,  ,  (the last of these is not an x-y graph in the usual sense,
but another way of plotting a bar chart), and  .
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Choose either a Normal Excel graph or
a Super Graph. A Super Graph allows you to 'freeze plots'.
This means that if the spreadsheet data changes, plots of the
new and old data both appear on the graph so that you can make
comparisons
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Say which column you want for the x-value (or
independent variable) axis by clicking in the x-axis space in
the box that appears, and then clicking on any cell in the x-value
column
- Click the Plot all rows button
(TIP If you only want to plot certain
rows, select the relevant rows in either the x-axis or y-axis
columns by clicking on the first value to be plotted, then holding
down Shift while you click on the last value to be plotted -
then choose Plot rows shown )
Changing the type of graph
Changing the x or y values plotted
Adding extra plots to a graph
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Click on any cell in the y-value (or dependent
variable) axis
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Click on the Add plot button 
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Say which column you want for the x-value
(or independent variable) axis by clicking in the x-axis space
in the box that appears, and then clicking on any cell in the
x-value column
Deleting plots on a graph
Forgotten where things are?
Click  and you will be shown where graph titles, axis labels, series
labels, names and tables are located.
How to write models or carry out calculations
based on data
What is involved
To write a spreadsheet based model (or to peform
calculations based on numerical data), one typically needs:
ImagineIT enables you to set up one or two
tables and one or two blocks of single-valued quantities,
all of which we will simply refer to as parameters
Here is a simple example:
1 Say where the table will be
First you must tell ImagineIT where your table
of values is to be. (Data must be arranged in columns, not
rows.)
Do one of the following:
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Either
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Select the whole table, excluding
column headings. (Hint: you can drag across the table with
the mouse to select it, or you can click in the top left
hand cell, then hold down shift while you click in the bottom
right hand cell.)
-
Click
2 Say where graph labels and column names
will go
Next identify the rows that you want to use for
graph titles, axis labels, 'series labels'
(labels that distinguish individual plots on one graph) and column
names (you can use these in formulae)
3 Say where parameters will go
Next identify the cells that you want to use for
parameters and parameter names (you can use these
in formulae)
- Click
 .
You will see a box on screen with spaces where
you can specify the row you want to use for parameter names, the
cell where you will put the first parameter value and the cell where
you will put the last parameter value. You do this by clicking in
the relevant cells on the spreadsheet. (You can leave any spaces
blank that you don't need.)
Write the model
Enter parameter and column names, numerical
data and formulae as needed. Here are a few tips:To
fill a column with the same formula, type it in the top cell and
then click  which means Copy down
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You can use words as well as algebraic
symbols to name quantities (but Excel won't let you use anything
that looks like a cell reference, such as b3 and the
two special letters c and r - which mean column
and row - you could use cc, rr, b.3 instead)
- You can use dots, underscores and capitals
to make names more readable, (e.g. a.2 or a_2 for
a2 and starting_amount or StartingAmount for the
starting amount of a quantity.
Draw appropriate graphs
Draw appropriate graphs using the instructions above
on How to explore data using graphs (leaving out the first
section - Setting up a table of data - since this has already been
done)
How to freeze plots or copies of plots on Super
Graphs
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Click on a single plot that you want to freeze,
or on a graph where you want to freeze all the plots, or on
the spreadsheet if you want to freeze all plots on all graphs.
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Click the Freeze plot button 
- Choose either Freeze or Freeze a copy
(which makes copies of the chosen plots, and then freezes them
- if you then make changes to the spreadsheet data, new plots
appear alongside the copies of the originals, so that you can
make comparisons)
(TIP You can tell the plots which have
been frozen because the series labels appear inside square brackets.)
How to delete frozen plots or copies of plots
on Super Graphs
Got in a mess with names?
Click  and all names will be deleted
except those currently given by the special names rows on
your spreadsheet (normally shown as red type on a pale blue background).
This is really useful if you have defined a lot of names while developing
your spreadsheet which you no longer need.
Be warned, however, that this will also
delete all additional names that you might have defined specially
which do not appear in the names rows.
Advanced modelling features
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Equally spaced values in a column
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Step by step calculations
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Iteration and random (Monte Carlo) simulations
Advanced modelling features
How does ImagineIT work?
ImagineIT is based on the simple idea that many
Excel procedures (such as drawing graphs and naming cells) are largely
about telling Excel where certain cells are to be found on your
spreadsheet.
With ImagineIT, by contrast, you say where key blocks
of cells are in advance. Thus, to make working with graphs
easy, you identify one or two tables of data on your spreadsheet
as ImagineIT tables, and, for each, say which rows you want
to use for graph titles, axis labels and labels to identify individual
data plots on any graph. Graphs can then be created, added
to, or altered with only two are three quick mouse clicks.
Similarly you identify one or two blocks of data
that you want to use for parameter values, and you identify which
rows you want to use to name these parameters, as well as the columns
in any ImagineIT tables. These names can then be used immediately
in formulae instead of cell references, making them much more readable.
Furthermore, should you want to change any names or add new ones,
the new names become usable straight away. This makes the
process of writing models much more agreeable and it makes the models
that you write much easier for other people to understand.
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, just the y-values 
, or both x and y-values, and possibly which rows are plotted
as well 
,
(or, for a normal Excel graph, you can simply press the Delete
button on your keyboard)