Difference between revisions of "Activities/Abacus/Abacos"

From Sugar Labs
Jump to navigation Jump to search
m (Add Header)
 
(8 intermediate revisions by 2 users not shown)
Line 1: Line 1:
[http://wiki.sugarlabs.org/go/Activities/Abacus English]
+
== Abacus/Abacos ==
[[File:Abacus.jpg]]
 
  
== Donde obtener la actividad Abacus ==
+
Read at https://help.sugarlabs.org/abacus.html
  
[http://activities.sugarlabs.org/en-US/sugar/addon/4293/ Activity] | [http://git.sugarlabs.org/projects/abacus/repos/mainline Source]
+
The source file has been moved to [https://github.com/godiard/help-activity/blob/master/source/abacus.rst GitHub]
 
 
== Acerca de los Ábacos ==
 
 
 
[[File:Abacus-icon.png]]
 
 
 
 
 
La Actividad Abacus refiere al [http://es.wikipedia.org/wiki/%C3%81baco ábaco], y permite al estudiante observar distintas formas de representar números usando estos antiguos dispositivos mecánicos desarrollados por todas las culturas. La Actividad trae variedades de ábacos bien distintas para explorar: [http://en.wikipedia.org/wiki/Suanpan Suanpan], el ábaco tradicional chino con 2 cuentas en la primer cubierta y 5 cuentas debajo; [http://en.wikipedia.org/wiki/Soroban Soroban], el ábaco tradicional japonés con 1 cuenta encima y 4 debajo; [http://en.wikipedia.org/wiki/Abacus#Russian_abacus Schoty], el ábaco tradicional ruso con 10 cuentas por columna y una columna con sólo 4 cuentas que se usaba para facilitar el denominador 4 en números mixtos; el [http://en.wikipedia.org/wiki/Abacus#Native_American_abaci Nepohualtzitzin], el ábaco tradicional maya con 3 cuentas encima y 4 debajo (base20). La Actividad Abacus incorpora también un ábaco binario (tradicional base 2), un ábaco hexadecimal (base 16) y tres ábacos que incluyen quebrados comunes: 1/2, 1/3, 1/4, 1/5, 1/6, 1/8, 1/9, 1/10, y 1/12, Fracciones, Caacupé y Cuisinaire. Desde la versión 9 Abacus incluye una barra de herramientas desde donde el estudiante puede diseñar el ábaco que quiera.
 
 
 
<gallery>
 
File:Suanpan.png|suanpan (Chino)
 
File:Soroban.png|soropan (Japonés)
 
File:Schety.png|schety (Ruso)
 
File:Nepohualtzintzin.png|nepohualtzintzin (Maya)
 
File:Binary.png|binario (Base 2)
 
File:Hexadecimal.png|hexadecimal (Base 16)
 
File:Fraction.png|fraccciones (1/2, 1/3, 1/4,..., 1/12)
 
File:Caacupe.png|Caacupe (1/2, 1/3, 1/4,..., 1/12 positivas y negativas)
 
File:Decimal.png|decimal (base 10)
 
File:Rods.png|cuisenaire (1/2, 1/3, 1/4,..., 1/12  estilo medidor cocina)
 
File:Custom-abacus.png|custom (Octal, base 8)
 
</gallery>
 
 
 
=== Las barras de herramientas ===
 
 
 
{| border=0
 
|-
 
|
 
[[Image:Abacus-main-toolbar.png|left]]
 
|-
 
|De izquierda a derecha:
 
* botón barra de actividad (etiquetar, compartir, guardar)
 
* botón saupan (ábaco chino)
 
* botón decimal (ábaco en sistema decimal)
 
* botón de adicionales (muestra un menú secundario con ábacos adicionales)
 
* botón barra de customización
 
* botón de parar -no se muestra en la figura-.
 
|-
 
|[[Image:Abacus-secondary-toolbar.png|left]]
 
|-
 
|De izquierda a derecha los ábacos adicionales:
 
* botón soroban (Ábaco japonés)
 
* botón schety (Ábaco ruso)
 
* botón nepohualtzintzin (Ábaco maya)
 
* botón binario (Ábaco binario)
 
* botón hexadecimal (Ábaco  hexadecimal)
 
* botón fracción (Ábaco fracciones)
 
* botón Caacupe (Ábaco fracciones negativas y positivas)
 
* botón Rodajas (Ábaco estilo cuisenaire)
 
|-
 
|[[Image:Abacus-custom-toolbar.png|left]]
 
|-
 
|De izquierda a derecha los parámetros de customización:
 
* elige el número de hileras
 
* elige el número de cuentas en las hileras del marco superior
 
* elige el número de cuentas en las hileras del marco inferior
 
* elige el factor de multiplicación para las hileras superiores (ejemplo, en el ábaco Chino, cada cuenta superior cuenta ×5 el valor de una cuenta inferior de su misma hilera)
 
* elige la base que determina el factor de multiplicación entre las hileras verticales de derecha a izquierda; este es 10 en los ábacos más convencionales (decimales),20 en el ábaco maya, 16 en el hexadecimal y 2 en el binario
 
* botón crear ábaco nuevo (debe presionarse para activar la selección creada)
 
|}
 
 
 
= Cómo usar un ábaco =
 
 
 
=== Setear el ábaco al inicio===
 
 
 
Antes de comenzar una operación aritmética es necesario "limpiar" el ábaco. Luego se colocan las cuentas superiores se colocan hacia arriba y inferiores hacia abajo. Esta es la posición por defecto del ábaco al iniciar la actividad. Tenga en cuenta que algunos ábacos (por ejemplo, el schety ruso) no tienen cuentas superiores. En estos casos, todas las cuentas comienzan abajo.
 
 
 
=== La lectura de ábacos ===
 
 
 
En ábacos tipo Suanpan con factor ×5 de abajo hacia arriba, las cuentas inferiores representan 1s y las superiores representan 5s. En la primer hilera cada cuenta inferior que sube suma 1, mientras cada cuenta superior que baja suma 5.
 
 
 
En los ábacos decimales, las posiciones de las hileras de derecha a izquierda representan las posiciones decimales enteras 1s, 10s, 100, 1000, etc.
 
Trabajando en otras bases como con (1) Nepohualtzintzin, que utiliza la base 20, las hileras de derecha a izquierda son potencias de 20 y sus cuentas valen 1s, 20s, 400s, 8000s, etc.
 
En el ábaco de Schety, (2) las cuentas a la derecha de la hilera distinta, de sólo 4 cuentas, valen décimos, centésimos, milésimos y diezmilésimos; mientras las de la izquierda son las decenas, centenas y demás posiciones decimales enteras.
 
En el ábaco Caacupé las cuentas en negro son fracciones de unidad y todas las cuentas pueden subir o bajar representando valores positivos y negativos.
 
El ábaco personalizado permite elegir la base y la disposición de las cuentas.
 
 
 
En el centro del marco siempre se desplega en números y sistema decimal el valor actual de las cuentas. Experimentando se aprende rapidamente a escribir y leer los números sobre los ábacos.
 
 
 
'''Examples:''' In the gallery below, several simple examples are shown. In the gallery of images above, the number 54321 is shown on each of the different abaci.
 
 
 
<gallery>
 
File:Abacus-1.png|1 bottom bead is up, corresponding to 1 unit
 
File:Abacus-5.png|1 top bead is down, corresponding to 5 units
 
File:Abacus-5b.png|5 bottom beads are up, also corresponding to 5 units
 
File:Abacus-6.png|1 bottom bead is up and 1 top bead is down, corresponding to 6 units
 
File:Abacus-10.png|5 bottom beads are up and 1 top bead is down, corresponding to 10 units (time to "carry" to the left)
 
File:Abacus-10x1.png|This 10 is equivalent to...
 
File:Abacus-1x10.png|... this 10
 
File:Abacus-54321.png|54321
 
</gallery>
 
 
 
'''Note:''' The display always assumes a fixed unit column, but you can override this choice.
 
 
 
<gallery>
 
File:Abacus-highlight.png|The beads moved most recently are highlighted.
 
</gallery>
 
 
 
=== Addition ===
 
 
 
To add, simply move in more beads to represent the number you are adding. There are two rules to follow: (1) whenever you have a total of 5 units or more on the bottom of a column, cancel out the 5 by sliding the beads back down and add a five to to the top; and (2) whenever you have a total of 10 units or more in a column, cancel out the 10 and add one unit to the column immediately to the left. (With the nepohualtzintzin, you work with 20 rather than 10.)
 
 
 
'''Example:''' 4+3+5+19+24=55
 
 
 
<gallery>
 
File:Abacus-plus-4.png|4
 
File:Abacus-plus-3.png|+3=7 (5–2=3)
 
File:Abacus-plus-5.png|+5=12
 
File:Abacus-12.png|carry 5s to next column
 
File:Abacus-plus-19.png|+19=31 (20-1=19)
 
File:Abacus-plus-24.png|+24=55
 
File:Abacus-55.png|4+3+5+19+24=55
 
</gallery>
 
 
 
=== Subtraction ===
 
 
 
Subtraction is the inverse of addition. Move out beads that correspond to the number you are subtracting. You can "borrow" from the column immediately to the left: subtracting one unit and adding 10 to the current column.
 
 
 
'''Example:''' 26–2–4–6–10=4
 
 
 
<gallery>
 
File:Abacus-26.png|26
 
File:Abacus-minus-2.png|26–2=24
 
File:Abacus-minus-4.png|24–4=20
 
File:Abacus-carry-10.png|carry 10 to the right
 
File:Abacus-minus-6.png|20–6=14
 
File:Abacus-minus-10.png|14–10=4
 
</gallery>
 
 
 
=== Multiplication ===
 
 
 
There are several strategies for doing multiplication on an abacus. In the method used in the example below, the multiplier is stored on the far left of the abacus and the multiplicand is offset to the left by the number of digits in the multiplier. The red ''indicator'' is used to help keep track of where we are in the process.
 
 
 
<gallery>
 
File:Abacus-486x24.png|486×24=? Begin by placing 24 in the left-most columns and 486 offset from the far right by two columns (since 24 has two digits). Set the indicator to the right of the multiplicand.
 
File:Abacus-4x6.png|Multiply the least-significant digits (LSD) of the multiplier (4) and multiplicand (6) and place the results (4×6=24) in the far right columns.
 
File:Abacus-2x6.png|Multiply the next digit in the multiplier (2, which corresponds to 2×10=20) and the LSD of the multiplicand (6) and add the results (2×6=12) on the right (advancing one column to the left to correspond to the power of the digit in the multiplier).
 
File:Abacus-100s.png|Move the indicator over one column to the left.
 
File:Abacus-4x8.png|Repeat for the next digit in the multiplicand (8): 4×8=32
 
File:Abacus-2x8.png|2×8=16
 
File:Abacus-1000s.png|Move the indicator over one column to the left.
 
File:Abacus-4x4.png|Repeat for the next digit in the multiplicand (4): 4×4=16
 
File:Abacus-2x4.png|2×4=8
 
File:Abacus-11664.png|Clear the multiplier from the left and view the result: 486×24=11664
 
</gallery>
 
 
 
=== Division ===
 
 
 
Simple division (by a single-digit number) is the inverse of multiplication. In the example below, the dividend is put on the left (leaving one column vacant for the quotient) and the divisor on the right.
 
 
 
<gallery>
 
File:Abacus-123456789-over-2.png|123456789÷2=? Place the dividend (123456789) on the left, leaving one blank column. Place the divisor (2) on the right.
 
File:Abacus-1-over-2.png|Working from the left to the right, divide a digit in the quotient and then move the indicator one column to the right. 1÷2=0.5
 
File:Abacus-2-over-2.png|2÷2=1
 
File:Abacus-3-over-2.png|3÷2=1.5
 
File:Abacus-4-over-2.png|4÷2=2
 
File:Abacus-5-over-2.png|5÷2=2.5
 
File:Abacus-6-over-2.png|6÷2=3
 
File:Abacus-7-over-2.png|7÷2=3.5
 
File:Abacus-8-over-2.png|8÷2=4
 
File:Abacus-9-over-2.png|9÷2=4.5
 
File:Abacus-617283945.png|The result is 61728394.5.
 
</gallery>
 
 
 
 
 
'''TODO:''' Add instructions for long division.
 
 
 
=== Fractions ===
 
 
 
The fraction abacus lets you add and subtract common fractions: 1/2, 1/3, 1/4, 1/5, 1/6, 1/8, 1/9, 1/10, and 1/12, The fractional value is determined by the number of black beads on a rod, e.g., to work with thirds, use the rod with three beads, to work with fifths, use the rod with five beads.
 
 
 
The rods with white beads are whole numbers in base 10; from left to right 100000, 10000, 1000, 100, 10, and 1.
 
 
 
<gallery>
 
File:Abacus-fractions.png|20 + 1 + 1/2 + 1/3 + 1/6 = 22
 
</gallery>
 
 
 
== Modifying Abacus ==
 
Abacus is under GPL license. You are free to use it and learn with it. You are also encouraged to modify it to suit your needs or just for a further opportunity to learn.
 
 
 
Most changes can be confined to three modules: <code>AbacusActivity.py</code>, <code>abacus.py</code> and <code>abacus_window.py</code>. The former define the Sugar and GNOME toolbars; the latter defines what code is executed by each type of abacus.
 
 
 
For instance, to add a menu item such as 'Reset' you would do the following in <code>abacus.py</code>:
 
 
 
* Add these lines to the menu items list:
 
        menu_items = gtk.MenuItem(_("Reset"))
 
        menu.append(menu_items)
 
        menu_items.connect("activate", self._reset)
 
 
 
* The _reset() method is trivial:
 
    def _reset(self, event, data=None):
 
        """ Reset """
 
        self.abacus.mode.reset_abacus()
 
 
 
Similarly, you can add another button to the Sugar toolbar in <code>AbacusActivity.py</code>:
 
 
 
* Add these lines to the toolbar block:
 
            # Reset the beads on the abacus to the initial cleared position
 
            self.reset_button = ToolButton( "reset" )
 
            self.reset_button.set_tooltip(_('Reset'))
 
            self.reset_button.props.sensitive = True
 
            self.reset_button.connect('clicked', self._reset_button_cb)
 
            toolbar_box.toolbar.insert(self.reset_button, -1)
 
            self.reset_button.show()
 
 
 
* The _reset_button_cb() method is trivial:
 
    def _reset_button_cb(self, event, data=None):
 
        """ Reset the beads on the abacus to the initial cleared position """
 
        self.abacus.mode.reset_abacus()
 
 
 
* You'll have to create an icon for the button (<code>reset.svg</code>) and put it into the <code>icon</code> subdirectory of the bundle.
 
 
 
This will complete the changes in the <code>abacus.py</code>. The method <code>reset_abacus()</code> will have to be defined for each abacus in the <code>abacus_window.py</code>.  This can be done by creating that method in the <code>AbacusGeneric</code> class used by all the varieties of abacus.  The method may have to be overridden in some abacus subclasses for customization reasons.  For instance, <code>reset_abacus()</code> was defined in <code>AbacusGeneric</code> class and then overridden in <code>Schety</code>.
 
 
 
If the changes involve modifying the graphics, then other methods may need to be modified as well.  For instance, in order to introduce a reset button that can be clicked to reset the bead positions to the beginning, the following methods had to be modified – all in <code>abacus_window.py</code>:
 
 
 
# in the <code>class Abacus</code>, method <code>_button_press_cb()</code> to activate reset button;
 
# in the <code>class AbacusGeneric</code>, method <code>create()</code> to create the graphics for reset button;
 
# methods <code>hide()</code> and <code>show()</code> to make the button visible.
 
 
 
==Discussion==
 
 
 
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).
 
 
 
Might be good to have some of the above information in Help, eg addition, subtraction, multiplication division. Just the text, no graphics?
 
 
 
It was proposed in IRC last night that a fun collaborative mode might be to have a number randomly generated and each sharer work independently to post it on the abacus of their choice first. There could be a tally of beads awarded for each correct answer. Maybe something to add to v10.
 
 
 
I wonder, should the beads on the fraction abacus vary in size? The halves should be five-bead heights each, for example?
 
 
 
As of v10, the beads are labeled.
 
 
 
== Reporting problems ==
 
If you discover a bug in the program or have a suggestion for an enhancement, please [https://bugs.sugarlabs.org/newticket?component=Abacus file a ticket] in our bug-tracking system.
 
 
 
You can [https://bugs.sugarlabs.org/query?status=accepted&status=assigned&status=new&status=reopened&component=Abacus view the open tickets here].
 
 
 
[[Category:Activities]]
 

Latest revision as of 22:48, 14 June 2018

Abacus/Abacos

Read at https://help.sugarlabs.org/abacus.html

The source file has been moved to GitHub