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Conversion Tool

Welcome to the Conversion Tool Help documentation. This is the on-line help file that accompanies the Conversion Tool software. You can use the menu below or displayed on the left of this page to navigate.

Click HELP! again or hit the ESCAPE key to return to the main screen.


Screenshot of Conversion Tool

Conversion Tool is a quick Window's conversion utility for all types of units of measure. Based on a customisable data file with an extensive list of even the most obscure units, it allows for multiple, simultaneous conversions. The data file also allows the definition of complex formula for conversion to and from a unit, significantly increasing the range of conversions possible.

Whilst Square One prides itself on having a very extensive range of conversions in the tool already, if you have a particularly obscure unit and the conversion data for it, please contact us as we will gladly add it to the collection. Alternatively, read the file format section below and you can add it yourself - but remember to share your new conversion with others using the Square One forum.

Entering a Unit

The quickest way to enter a unit is simple to type the value followed by its abbreviation in the Value textbox. As you type, Conversion Tool will try to find the closest matching unit and display a dynamic list of partial matches in the list below. When unit abbreviations are displayed in blue, you can use the Up and Down Arrow keys to select from the partial match list.

Once you have the right units selected or entered, hit the Enter key to perform the conversion and display the results.

Selecting a Unit

To select the desired unit manually, first choose from the available Units Categories in the left-most selection list. For example, if you wanted to convert acres to hectares, first select Surface Area from the Units Categories list. The available units in that category will then be shown in middle list and the Value textbox will default to the SI units for that group.

You can then select the particular unit you are interested in from either the Units List or the Results list. If you click on the unit in the Results list, the Value textbox will change to that for the selected unit.

Entering Values and Equations

To change the value of the selected unit, type a new value in the Value edit box. The entered string is first passed through the equation interpreter (yes - I had to write my own parser) so you can enter an equation of any complexity using brackets and mathematical functions. For example, try typing 10*log(12/(15-3)) + (sin(pi/12) * 10^6) into this edit box and then press the Enter key.

An equation can consist of up to 128 alphanumeric characters or spaces. It can contain any of the functions shown below.

Available Math Functions
EXP() LOG() LN()
+ - */ () ^ PI

NOTE: Basically it's your job to let the tool know when you have finished editing the value text and require an update of the results. You can do this by hitting the Enter key, the Tab key or by clicking the left mouse button in another area of the application window. Hitting the Escape key at any time will set the focus to the Value textbox so you can immediately enter a new value. When entering unit abbreviations, only the Enter key or double-clicking the required units in the partial match list will update the selection.

Searching for Units

If you are unsure of the category in which to find a unit, simply select the SEARCH button at the top of the window. This will display a dialogue box with a list of all available units. You can scroll through the list or type in the first few letters of the unit you are searching for. If it is there, it will appear immediately below the edit box in the scrolling list. It is important that you actually select the one you want before hitting the OK button - having it displayed is not enough. When you do select a unit and hit OK, the appropriate group will be displayed and the conversion performed.

Data File Format

All of the units used by Conversion Tool and their conversion factors are stored in the file ConversionTool.dat. For maximum flexibility, this is in simple ASCII format and based on tokens to indicate unit data and categories. A token is simply a recognisable string ending with a full colon. Each token is followed by a specific set of data which is then read. Whilst the usual comment characters ( #, /*, */ and // ) are all recognised, such a format allows other text to be placed anywhere within the file as long as it is not between a token and it's data.

As it is a simple ASCII file, you can edit it to add units or categories of units should the need arise. In order to do this successfully, you will need to familiarise yourself with the available tokens.

This token indicates a new group. The name can consist of up to 80 characters and spaces ending with a new-line. All subsequent tokens in the file will belong to this group. The first unit following a group is taken as the base units for that group and must therefore have a value of 1.0 as its conversion factor. The conversion factors of all subsequent units in that group are taken to refer to this unit. Whilst not absolutely necessary, it is recommended that this be an SI unit.
<type> <factor> <name>
This specifies a unit with a simple linear relationship with the base unit. The <type> parameter specifies the type of unit, as laid out in the results list. It can be any of the following values:
SI Base - International System of Units
M Metric Unit
I Imperial Unit
C Constant Value
O Other...
The <factor> parameter is a single floating point number of any precision. The <name> parameter can consist of up to 80 characters and spaces ending with a new-line. The standard abbreviation for the unit, if there is one, should be included after the name inside brackets.
<type> <to> <from> <name>
This specifies a unit with a more complex relationship with the base unit. In this case the <to> and <from> parameters refer to equations converting the unit to and from the base units. As a result, the first unit following a new category cannot be a formula. The <name> parameter can consist of up to 80 characters and spaces ending with a new-line. The standard abbreviation for the unit, if there is one, should be included after the name inside brackets.
An example is the conversion data from Kelvin to Fahrenheit which apears in the data file. You should study this example if you intend adding your own complex formula-based conversions.
formula: I (((x-273)/(5/9.0))+32) ((x-32)*(5/9.0))+273 Fahrenheit (F)
An equation in the file can consist of up to 128 characters but no white spaces. It can contain any of the mathematical functions described above as well as X which is used to indicate the value text.
You must enter two formula as Conversion Tool needs to be able to convert both to and from any unit. As formula are read in as strings and parsed each time a calculation is required, it seemed an extraordinarily difficult task to derive the reverse conversion from the various operations it contains. I looked at this briefly and decided it was much easier to simply require two formula :).
NOTE: It is vitally important that each formula be the exact reverse of each other. The first converts the specified unit to the base units of its group (X represents the specified unit) whereas the second converts the base units to the specified unit (X represents the base units). You should use the existing formula in the data file supplied as a guide.

Related Information

Decimal Prefixes
Prefixes are often used to express decimal multiples of units instead of powers of 10. Their names and symbols are listed below:
Name Symbol Factor
tera T 10E12
giga G 10E9
mega M 10E6
kilo k 10E3
hecto h 10E2
deca da 10
deci d 10E-1
centi c 10E-2
milli m 10E-3
micro u 10E-6
nano n 10E-9
pico p 10E-12
femto f 10E-15
atto a 10E-18
Decimal prefixes and their values
SI Units
SI is an abbreviation of the French 'Systeme International d'Unites' or International System of Units. At the time of writing, it currently consists of seven basic quantities:
Quantity Units Symbol
Length metres m
Mass kilogram kg
Time second s
Electric Current ampere A
Temperature Kelvin K
Luminous Intensity candela cd
Substance mole mol
SI base quantities and units
- two supplementary quantities:
Quantity Units Symbol
Plane angle radian rad
Solid Angle steradian sr
SI supplementary units
and a host of derived units.


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