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And so on | And so on | ||
We notice that the last rotate position by 1, the fifth rotate position by 2, the fourth rotate position by 3, the third rotate position by 4, the second rotate position by 5 and first rotate position by 6. | We notice that the last rotate position by 1, the fifth rotate position by | ||
2, the fourth rotate position by 3, the third rotate position by 4, the | |||
second rotate position by 5 and first rotate position by 6. | |||
So we can write down a simple formula: | So we can write down a simple formula: | ||
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=720 | =720 | ||
This kind of arragenment of things around some position, where position number is equal of number of things is called "permutation" | This kind of arragenment of things around some position, where position | ||
number is equal of number of things is called "permutation" | |||
Let's try to call in kalgebra the permutation function: | Let's try to call in kalgebra the permutation function: | ||
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Let's roll a dice, we want to know the probability of one face | Let's roll a dice, we want to know the probability of one face | ||
We can define positive probability the favourble result of the event to us and negative probability the unfavorable result of the event to us | We can define positive probability the favourble result of the event to us | ||
and negative probability the unfavorable result of the event to us | |||
So you have to pick only one face: | So you have to pick only one face: | ||
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probability = 1(face picked)/6(total face) | probability = 1(face picked)/6(total face) | ||
So now we know that when a dice is rolled there is a 1/6 of probability that a face we choice come up | So now we know that when a dice is rolled there is a 1/6 of probability that | ||
a face we choice come up | |||
We can set a simple function in kalgebra to take this formula in a simple way: | We can set a simple function in kalgebra to take this formula in a simple | ||
way: | |||
probability:=(favorable,total)->favorable/total | probability:=(favorable,total)->favorable/total | ||
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=== Numerical Theory === | === Numerical Theory === | ||
Let's say that we want to know the sum of all numbers between a bounded interval | Let's say that we want to know the sum of all numbers between a bounded | ||
for istance 1 - 100 | interval for istance 1 - 100 | ||
we have to do the sum of all numbers from 0 to 100 if we don't know the rule to get them | we have to do the sum of all numbers from 0 to 100 if we don't know the | ||
rule to get them | |||
kalgebra offers a great facility to this task. Let's write in console: | kalgebra offers a great facility to this task. Let's write in console: | ||
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Example2: | Example2: | ||
We have a simple circuit: a battery of 3V and two eletrical resistence (R1 and R2) put on parallel of 3kohm. We want to get the current circulating in the circuit. | We have a simple circuit: a battery of 3V and two eletrical resistence | ||
(R1 and R2) put on parallel of 3kohm. We want to get the current | |||
circulating in the circuit. | |||
We have first to calculate the value of the eletric resistence expressed as the law: | We have first to calculate the value of the eletric resistence expressed | ||
as the law: | |||
TotalResistence = (1/R1 + 1/R2)^-1 | TotalResistence = (1/R1 + 1/R2)^-1 |
Latest revision as of 20:43, 4 December 2010
This page show some use of kalgebra in real word
Combinatorial example
We have 6 people who want to know how to get around a table with 6 chairs.
We now that 6 people can get around the table with this configuration
p1 p2 p3 p4 p5 p6 p1 p2 p3 p4 p6 p5 p1 p2 p3 p5 p4 p6 p1 p2 p3 p5 p6 p4
And so on
We notice that the last rotate position by 1, the fifth rotate position by 2, the fourth rotate position by 3, the third rotate position by 4, the second rotate position by 5 and first rotate position by 6.
So we can write down a simple formula:
6*5*4*3*2*1
Let's write this into kalgebra console:
((((1*2)*3)*4)*5)*6
=720
This kind of arragenment of things around some position, where position number is equal of number of things is called "permutation"
Let's try to call in kalgebra the permutation function:
factorial(6)
=720
It's the same result as you can see.
Probability example
Let's roll a dice, we want to know the probability of one face We can define positive probability the favourble result of the event to us and negative probability the unfavorable result of the event to us
So you have to pick only one face:
probability = 1(face picked)/6(total face)
So now we know that when a dice is rolled there is a 1/6 of probability that a face we choice come up
We can set a simple function in kalgebra to take this formula in a simple way:
probability:=(favorable,total)->favorable/total
Numerical Theory
Let's say that we want to know the sum of all numbers between a bounded interval for istance 1 - 100
we have to do the sum of all numbers from 0 to 100 if we don't know the rule to get them kalgebra offers a great facility to this task. Let's write in console:
sum(x: x=1.100) and we get the result
The syntax indicate this:
1- Bound x as variable 2- Take first value of x 3- Take second value of x and add the previus value of x 4- Take third value of x and add the previus value of x .... N- Take the last value of x and add the last value of x
Eletronic
Example1:
Let's take a simple circuit a and port with two input and one output
To resolve it on kalgebra we will write
and(variable1, variable2)
we will get the and value of the input as output
Example2: We have a simple circuit: a battery of 3V and two eletrical resistence (R1 and R2) put on parallel of 3kohm. We want to get the current circulating in the circuit.
We have first to calculate the value of the eletric resistence expressed as the law:
TotalResistence = (1/R1 + 1/R2)^-1 Current = Voltage/TotalResistence
Let's write a simple function in kalgebra to do this:
totalresistence:=(R1,R2)->(1/R1+1/R2)^-1 current:=(voltage,totalresistence)->voltage/totalresistence
let's see what we get:
current(3, totalresistence(3, 3)) =2