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== About Abacus ==
== About Abacus ==
[[File:Abacus-icon.png]]
[[File:Abacus-icon.png]]
[http://en.wikipedia.org/wiki/Abacus Abacus] lets the learner explore different representations of numbers using different mechanical counting systems developed by the ancient Romans and Chinese. There are several different variants available for exploration: a [http://en.wikipedia.org/wiki/Suanpan suanpan], the traditional Chinese abacus with 2 beads on top and 5 beads below; a [http://en.wikipedia.org/wiki/Soroban soroban], the traditional Japanese abacus with 1 bead on top and 4 beads below; the [http://en.wikipedia.org/wiki/Abacus#Russian_abacus schety], the traditional Russian abacus, with 10 beads per column, with the exception of one column with just 4 beads used for counting in fourths; and the [http://en.wikipedia.org/wiki/Abacus#Native_American_abaci nepohualtzintzin], a Mayan abacus, 3 beads on top and 4 beads below (base 20). There is also a binary abacus, a hexadecimal abacus, and several abacuses that lets you calculate with common fractions: 1/2, 1/3, 1/4, 1/5, 1/6, 1/8, 1/9, 1/10, and 1/12. As of Version 9, there is a customization toolbar that lets you design your own abacus. There is an [[Activities/Yupana|Incan abacus (Yupana)]] as a standalone program.
[http://en.wikipedia.org/wiki/Abacus Abacus] lets the learner explore different representations of numbers using different mechanical counting systems developed by the ancient Romans and Chinese. There are several different variants available for exploration: a [http://en.wikipedia.org/wiki/Suanpan suanpan], the traditional Chinese abacus with 2 beads on top and 5 beads below; a [http://en.wikipedia.org/wiki/Soroban soroban], the traditional Japanese abacus with 1 bead on top and 4 beads below; the [http://en.wikipedia.org/wiki/Abacus#Russian_abacus schety], the traditional Russian abacus, with 10 beads per column, with the exception of one column with just 4 beads used for counting in fourths; and the [http://en.wikipedia.org/wiki/Abacus#Native_American_abaci nepohualtzintzin], a Mayan abacus, 3 beads on top and 4 beads below (base 20). There is also a binary abacus, a hexadecimal abacus, and several abacuses that lets you calculate with common fractions: 1/2, 1/3, 1/4, 1/5, 1/6, 1/8, 1/9, 1/10, and 1/12. As of Version 9, there is a customization toolbar that lets you design your own abacus. There is an [[Activities/Yupana|Incan abacus (Yupana)]] as a standalone program.
[http://wiki.sugarlabs.org/go/Activities/Abacus/Abacos Traducción español] |
[[File:Abacus.jpg]]
File:Suanpan.png|suanpan (Chinese)
=== The toolbars ===
== Where to get Abacus ==
[http://activities.sugarlabs.org/en-US/sugar/addon/4293/ Activity] | [http://git.sugarlabs.org/projects/abacus/repos/mainline Source]
[[Image:Abacus Toolbar 1.png]]
|[[Image:Abacus Toolbar 2.png]]
== How to use an abacus ==
== Using Abacus ==
=== Clear the abacus ===
=== Clearing the abacus ===
Before you start an arithmetic operation, you need to "clear" the abacus. The upper beads should be positioned against the top of the frame and the lower beads should be positioned against the bottom of the frame. This is the default position for the abacus when you launch the activity. (Note that some of the abacuses (e.g., the schety) do not have any upper beads. In such cases, all of the beads should start in the down position.)
Before you start an arithmetic operation, you need to "clear" the abacus. The upper beads should be positioned against the top of the frame and the lower beads should be positioned against the bottom of the frame. This is the default position for the abacus when you launch the activity. (Note that some of the abacuses (e.g., the schety) do not have any upper beads. In such cases, all of the beads should start in the down position.)
File:Abacus-617283945.png|The result is 61728394.5.
File:Abacus-617283945.png|The result is 61728394.5.
</gallery>
</gallery>
'''TODO:''' Add instructions for long division.
'''TODO:''' Add instructions for long division.
# methods <code>hide()</code> and <code>show()</code> to make the button visible.
# methods <code>hide()</code> and <code>show()</code> to make the button visible.
==Discussion==
=== The toolbars ===
{| border=0
|-
|
[[Image:Abacus Toolbar 1.png]]
|-
|From left to right:
* project-toolbar button
* edit-toolbar button
* abacus-toolbar button
* customization-toolbar button
* clear button (clear the abacus)
* stop button
|-
|[[Image:Abacus Toolbar 2.png]]
|-
|From left to right:
* copy (copy current value to clipboard)
* paste (paste a value from the clipboard into the abacus)
|-
|[[Image:Abacus Toolbar 3.png]]
|-
|From left to right:
* decimal button (decimal abacus)
* soroban button (Japanese abacus)
* saupan button (Chinese abacus)
* nepohualtzintzin button (Mayan abacus)
* hexadecimal button (hexadecimal abacus)
* binary button (binary abacus)
* schety button (Russian abacus)
* fraction button (fraction abacus)
* Caacupe button (fraction abacus with +/–)
* rod button (Cuisenaire-like abacus)
* custom button (your custom abacus)
|-
|[[Image:Abacus Toolbar 4.png]]
|-
|From left to right:
* select the number of rods
* select the number of beads on the top of the frame
* select the number of beads on the bottom of the frame
* select the multiplication factor of top beads (e.g., on the Chinese abacus, each top bead counts as 5× the value of a bottom bead on the same rod)
* select the base to determine the value of bottom beads across rods; this is 10 on most conventional abacuses, but 20 on the Mayan abacus, 16 on the hexadecimal abacus, and 2 on the binary abacus.
* new-abacus button (you must push this button to activate the selections you've made)
|}
<gallery>
File:Suanpan.png|suanpan (Chinese)
File:Soroban.png|soropan (Japanese)
File:Schety.png|schety (Russian)
File:Nepohualtzintzin.png|nepohualtzintzin (Mayan)
File:Binary.png|binary (base 2)
File:Hexadecimal.png|hexadecimal (base 16)
File:Fraction.png|fractions (1/2, 1/3, 1/4,...)
File:Caacupe.png|Caacupe (fractions with +/–)
File:Decimal.png|decimal (base 10)
File:Rods.png|Cuisenaire-style rods (fractions)
File:Custom-abacus.png|custom, as shown: octal (base 8)
</gallery>
==Learning with Abacus==
It would be interesting to discuss [[Activities/Abacus/Worksheet |various lesson plans]] for using an abacus here. Also, it would be interesting to explore the use of color. What if, for example, the more recent a bead is moved, the more colorful it is? (implemented in v5). This would perhaps make it more clear what the order of operations is on a calculation. Also, what it we extend the idea of the schety to include more fractional components, e.g., 3rd, 5ths, 6ths, etc. and perhaps have a mode where we can automate the consolidation of the fractional parts (implemented in v6).
It would be interesting to discuss [[Activities/Abacus/Worksheet |various lesson plans]] for using an abacus here. Also, it would be interesting to explore the use of color. What if, for example, the more recent a bead is moved, the more colorful it is? (implemented in v5). This would perhaps make it more clear what the order of operations is on a calculation. Also, what it we extend the idea of the schety to include more fractional components, e.g., 3rd, 5ths, 6ths, etc. and perhaps have a mode where we can automate the consolidation of the fractional parts (implemented in v6).
As of v10, the beads are labeled.
As of v10, the beads are labeled.
==Extending Abacus==
* A fun project is to compare calculations using Abacus with the Calculate Activity. Which is faster? Which is more accurate? Which is better for estimating? Which is better for comparing?
* Abacus supports paste, so you can take numeric values from other programs and paste them into the abacus to see what their representations are; for example, I often paste numbers into the hexadecimal abacus as a quick way of converting decimal to hexidecimal.
* Abacus also supports copy, so you can take a sum calculated on an abacus and export it into SimpleGraph or some other data-visualization Activities.
== Reporting problems ==
== Reporting problems ==