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Offline tomatogoatee  
#1 Posted : 06 July 2009 23:52:24(UTC)
tomatogoatee

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First, let me say my knowledge of math doesn't extend very far past High School. For what I don't know, a quick trip to Wikipedia will enlighten me enough to get through my problem.

That being said, I am fascinated by this app. The number of calculation possibilities is staggering. And on top of what this app is capable of, it being free software just blows my mind. I'd like to thank the author for all his time and effort.

Now for my question. How do you express subscript numbers? Such as:
a_n = n(n-8.6)
a_10 = 14

It would seem I also don't know how to express subscript in BBCode. Nor am I able to find anything that works correctly.
Offline omorr  
#2 Posted : 07 July 2009 00:20:42(UTC)
omorr


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Try this
n←5
a←matrix(n;1)
You will have a matrix with n rows and 1 column filled with zeros (SMath only knows about matrices - vectors are not introduced yet)
And then this
el(a;n;1)←n*(n+8)
el(a;2;1)←5
a=mat(0;5;0;0;65;5;1)

Definition - ":=" and Evaluate numericaly - "=" you will find in Arithmetic palete. Indices (two of them) you can get by "el" function under Function palete or just press "["

Pay attention what the Argument splitter in "matrix" function is. It could be ";" or "," depending on your regional settings (look in the Arithemtic palete what you see after "x" - Multiplication )

Regards,
Radovan

P.S. If you want to see the /BB codes in this message just use "QUOTE" the messages. Inside MATH code the expressions are just copied and pasted from SMath. But to see them corectly in the forum messages, argument splitters must be ";" (you can change it manualy)

Edited by user 07 July 2009 00:25:14(UTC)  | Reason: Not specified

When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"
Offline tomatogoatee  
#3 Posted : 07 July 2009 01:23:00(UTC)
tomatogoatee

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Maybe I wasn't exactly clear on my question. How do you enter subscript in smath? The actual sub n or 1 in:
el(a;n;1)←n*(n+8)
There's a button to enter exponents, but none for subscript.
Offline omorr  
#4 Posted : 07 July 2009 01:34:20(UTC)
omorr


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tomatogoatee wrote:
Maybe I wasn't exactly clear on my question. How do you enter subscript in smath? The actual sub n or 1 in:
el(a;n;1)←n*(n+8)
There's a button to enter exponents, but none for subscript.

Just pres the left square bracket "[" and you will see three placeholder. The first is the name of the matrix, the second is the row index and the third the column index. Is this what you want?

Regards,
Radovan
When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"
Offline tomatogoatee  
#5 Posted : 07 July 2009 01:53:30(UTC)
tomatogoatee

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Well, yes and no. Yes, in that the [ character does what you described (I'm using the PPC version. I probably should have mentioned that.) but I just realized what I wanted to do didn't even require subscript characters nor matrices to begin with...

f(n)=n(n-8.6)
f(10)=14

is what I simply needed. I was thinking, for some reason, that a subscript number was required because that is what was used in the equation I was trying to enter.

This is just an example of my mathematical naiveté. Sorry to have wasted your time.
Offline omorr  
#6 Posted : 07 July 2009 02:10:24(UTC)
omorr


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tomatogoatee wrote:
Well, yes and no. Yes, in that the [ character does what you described (I'm using the PPC version. I probably should have mentioned that.) but I just realized what I wanted to do didn't even require subscript characters nor matrices to begin with...

f(n)=n(n-8.6)
f(10)=14

is what I simply needed. I was thinking, for some reason, that a subscript number was required because that is what was used in the equation I was trying to enter.

This is just an example of my mathematical naiveté. Sorry to have wasted your time.

Do not worry about that. Just ask!
You need to define a function. It is simple.
f(n)←n*(n-8,6)
(Pay attention - you might have to put 8.6 not 8,6)
and call it
f(10)=14
You can even drow it. Just choose 2D (or press "@" ) and in the placeholder (lower left corner of the plot) put f(x) - pay attention it must be "x" not "n"

Regards,
Radovan
When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"
Offline tomatogoatee  
#7 Posted : 07 July 2009 02:29:52(UTC)
tomatogoatee

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omorr wrote:
tomatogoatee wrote:
(Pay attention - you might have to put 8.6 not 8,6)

I'm in the US. Wink Good tip, though. I wonder how often that comes up as a problem. (Probably not too frequently, seeing how the vast majority of people who would be using this program would know better.)
Offline omorr  
#8 Posted : 07 July 2009 02:53:22(UTC)
omorr


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It is quite simple. It depends on your Regional Settings
If you are in US you will see this

Decimal point is "." and Argument separator is "," (blue square)
If you are in some other part of the world (German or Eastern states) you will probebly see
Decimal point is "," and Argument separator is ";" (blue square)

Regards,
Radovan
When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"
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