how to use {fancu}?

[Gleki Arxokuna]

How to say e.g. "f(x) = (x + 1) (x − 1)" ? Should I use {fancu} for that? If not how to use {fancu}?

I want an example with all places of {fancu} filled.

fancu = x1 is a function/single-valued mapping from domain x2 to range x3 defined by expression/rule x4.

E.g "f(x) = (x + 1) (x − 1)" where x>1

fy fancu xy lo du'u xy zmadu li pa vau li vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o ?

[Jorge Llambías]

We need to distinguish three cases:

(1) example of what the gimste says it means

(2) example of what "fancu" ought to mean

(3) example of actual usage

If you want (1), you could say:

 fy fancu lo'i mrena'u poi zmadu li pa lo'i mrena'u poi zmadu li no me'o vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o

You want "me'o", not "li", for an expression. I'm assuming you meant it as a function on the reals and not, for example on the integers. The domain of the function is the set of values for which the function is defined. The range is the set from which the function takes its values. In this case it could also have been all the reals, even though the function never takes negative values. lo'i mrena'u poi zmadu li no is the image, which has to be included in the range. It doesn't say anywhere that "xy" is the variable that will take its values from the domain, but using x as a variable is of course a very common convention.

As for (2): It doesn't really make a lot of sense to me to have a place for expression x4 in addition to a place for the function. It's as if "klama" was defined as "x1 goes to x2 ... and has name x6". The place for the range is also redundant. It's as if "jalge" was defined as "x1 is the result of x2 among potential results x3", or something like that. "fancu" ought to have just two places: "x1 is a function of x2". Your example would be: "fy pe xy du li vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o", which doesn't use "fancu", but you could also say fy fancu xy noi mrena'u gi'e zmadu li pa". A more general use would be:

 

 lo jdima be lo seldi'a cu fancu lo ni sy se sabji jo'u lo ni sy se cpedu

 "The price of a good is a function of its supply and demand."

Finally (3), usage, is all over the place. An example from Tatoeba (just because it's the first hit for "cu fancu" that I get from Google):

  ro da poi fancu lo nuncfa cu fancu lo nunfa'o
  Whatever is subject to origination is all subject to cessation.

But I don't really see how "fancu" can be "subject to". To me that says that every thing that depends on a start, depends on having (or being?) an end. "Being subject to" is more like "lifri". I would say: "ro da poi lifri lo ka cfari cu lifri lo ka tolcfa".

mu'o mi'e xorxes

[Jacob Errington]

On 17 September 2014 11:23, Jorge Llambías <jjlla...@gmail.com> wrote:

As for (2): It doesn't really make a lot of sense to me to have a place for expression x4 in addition to a place for the function. It's as if "klama" was defined as "x1 goes to x2 ... and has name x6". The place for the range is also redundant. It's as if "jalge" was defined as "x1 is the result of x2 among potential results x3", or something like that. "fancu" ought to have just two places: "x1 is a function of x2".

 In that case, I wonder what the type of the x1 could be. Is it a function in the sense of a ka abstraction? I would find this strikingly useful. Alas, that's not what you used for your example. I think I would have written it ".i lo ka makau jdima ce'u cu fancu lo ni ce'u se sabji gijo'u jai se cpedu". The major limitation here is that there's no obvious way to actually refer to the things themselves, so the place for the domain becomes useful with this formalism, since saying that this function actually applies to some concrete object would amount to stating that the object is in the domain of this function.

This also gives us a neat way of saying things like "How likely I am to do something depends on how much I want to do it," as ".i lo ni lakne fa lo nu mi ce'u zukte cu fancu lo ni mi djica co zukte ce'u" all the while avoiding lo-sumti altogether, simply talking about how these functions relate.

.i mi'e la tsani mu'o

[Jorge Llambías]

On Wed, Sep 17, 2014 at 5:23 PM, Jacob Errington <nict...@gmail.com> wrote:

On 17 September 2014 11:23, Jorge Llambías <jjlla...@gmail.com> wrote:

 "fancu" ought to have just two places: "x1 is a function of x2".

 In that case, I wonder what the type of the x1 could be. Is it a function in the sense of a ka abstraction? I would find this strikingly useful. Alas, that's not what you used for your example. I think I would have written it ".i lo ka makau jdima ce'u cu fancu lo ni ce'u se sabji gijo'u jai se cpedu".

I think it can work both ways: property function of property, or thing function of thing. 

The major limitation here is that there's no obvious way to actually refer to the things themselves, so the place for the domain becomes useful with this formalism, since saying that this function actually applies to some concrete object would amount to stating that the object is in the domain of this function.

Not sure I follow what you have in mind.

 

This also gives us a neat way of saying things like "How likely I am to do something depends on how much I want to do it," as ".i lo ni lakne fa lo nu mi ce'u zukte cu fancu lo ni mi djica co zukte ce'u" all the while avoiding lo-sumti altogether, simply talking about how these functions relate.

Right.  

[Gleki Arxokuna]

2014-09-17 19:23 GMT+04:00 Jorge Llambías <jjlla...@gmail.com>:

On Wed, Sep 17, 2014 at 3:35 AM, Gleki Arxokuna <gleki.is...@gmail.com> wrote:

How to say e.g. "f(x) = (x + 1) (x − 1)" ? Should I use {fancu} for that? If not how to use {fancu}?

I want an example with all places of {fancu} filled.

fancu = x1 is a function/single-valued mapping from domain x2 to range x3 defined by expression/rule x4.

E.g "f(x) = (x + 1) (x − 1)" where x>1

fy fancu xy lo du'u xy zmadu li pa vau li vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o ?

We need to distinguish three cases:

(1) example of what the gimste says it means

(2) example of what "fancu" ought to mean

(3) example of actual usage

If you want (1), you could say:

 fy fancu lo'i mrena'u poi zmadu li pa lo'i mrena'u poi zmadu li no me'o vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o

You want "me'o", not "li", for an expression. I'm assuming you meant it as a function on the reals and not, for example on the integers. The domain of the function is the set of values for which the function is defined. The range is the set from which the function takes its values. In this case it could also have been all the reals, even though the function never takes negative values. lo'i mrena'u poi zmadu li no is the image, which has to be included in the range. It doesn't say anywhere that "xy" is the variable that will take its values from the domain, but using x as a variable is of course a very common convention.

As for (2): It doesn't really make a lot of sense to me to have a place for expression x4 in addition to a place for the function. It's as if "klama" was defined as "x1 goes to x2 ... and has name x6". The place for the range is also redundant. It's as if "jalge" was defined as "x1 is the result of x2 among potential results x3", or something like that. "fancu" ought to have just two places: "x1 is a function of x2". Your example would be: "fy pe xy du li vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o"

Don't you think {pe} is extremely hackish here?

 

, which doesn't use "fancu", but you could also say fy fancu xy noi mrena'u gi'e zmadu li pa"

And this doesn't use the formula.

Still I think "f(x) is the name for "(x+1)(x-1)"" is a useful predicate.

 

. A more general use would be:

 

 lo jdima be lo seldi'a cu fancu lo ni sy se sabji jo'u lo ni sy se cpedu

 "The price of a good is a function of its supply and demand."

This just needs a separate brivla.

Finally (3), usage, is all over the place. An example from Tatoeba (just because it's the first hit for "cu fancu" that I get from Google):

  ro da poi fancu lo nuncfa cu fancu lo nunfa'o
  Whatever is subject to origination is all subject to cessation.

But I don't really see how "fancu" can be "subject to". To me that says that every thing that depends on a start, depends on having (or being?) an end. "Being subject to" is more like "lifri". I would say: "ro da poi lifri lo ka cfari cu lifri lo ka tolcfa".

mu'o mi'e xorxes

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[Jorge Llambías]

On Thu, Sep 18, 2014 at 2:41 AM, Gleki Arxokuna <gleki.is...@gmail.com> wrote:

2014-09-17 19:23 GMT+04:00 Jorge Llambías <jjlla...@gmail.com>:

On Wed, Sep 17, 2014 at 3:35 AM, Gleki Arxokuna <gleki.is...@gmail.com> wrote:

E.g "f(x) = (x + 1) (x − 1)" where x>1

Your example would be: "fy pe xy du li vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o"

Don't you think {pe} is extremely hackish here?

No, I think it's correct, "the f associated with x is equal to x plus one times x minus one". 

, which doesn't use "fancu", but you could also say fy fancu xy noi mrena'u gi'e zmadu li pa"

And this doesn't use the formula.

You can combine both: 

  fy pe xy zi'e no'u li vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o cu fancu xy noi mrena'u gi'e zmadu li pa

 

Still I think "f(x) is the name for "(x+1)(x-1)"" is a useful predicate.

f(x) is not the name for "(x+1)(x-1)", it's the other way around.

"f(x)", or "(x+1)(x-1)", are two different names, or descriptions, of the same function: f(x), or (x+1)(x-1). 

The description "(x+1)(x-1)" is just more descriptive because it uses more conventional symbols, whereas the description "f(x)" uses a nonce symbol. The advantage of "f(x)" is that it's shorter, so if we are going to be using the function conventionally described as "(x+1)(x-1)" a lot, it may be useful to assign it a shorter name, such as "f(x)". It's like "ko'a" and "lo nanmu poi bevri lo pipno", one is more descriptive and the other is shorter, but they can both be used to refer to the same thing(s).

[la gleki]

On Thursday, September 18, 2014 9:41:32 AM UTC+4, la gleki wrote:

2014-09-17 19:23 GMT+04:00 Jorge Llambías <jjlla...@gmail.com>:

On Wed, Sep 17, 2014 at 3:35 AM, Gleki Arxokuna <gleki.is...@gmail.com> wrote:

How to say e.g. "f(x) = (x + 1) (x − 1)" ? Should I use {fancu} for that? If not how to use {fancu}?

I want an example with all places of {fancu} filled.

fancu = x1 is a function/single-valued mapping from domain x2 to range x3 defined by expression/rule x4.

E.g "f(x) = (x + 1) (x − 1)" where x>1

fy fancu xy lo du'u xy zmadu li pa vau li vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o ?

We need to distinguish three cases:

(1) example of what the gimste says it means

(2) example of what "fancu" ought to mean

(3) example of actual usage

If you want (1), you could say:

 fy fancu lo'i mrena'u poi zmadu li pa lo'i mrena'u poi zmadu li no me'o vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o

You want "me'o", not "li", for an expression. I'm assuming you meant it as a function on the reals and not, for example on the integers. The domain of the function is the set of values for which the function is defined. The range is the set from which the function takes its values. In this case it could also have been all the reals, even though the function never takes negative values. lo'i mrena'u poi zmadu li no is the image, which has to be included in the range. It doesn't say anywhere that "xy" is the variable that will take its values from the domain, but using x as a variable is of course a very common convention.

As for (2): It doesn't really make a lot of sense to me to have a place for expression x4 in addition to a place for the function. It's as if "klama" was defined as "x1 goes to x2 ... and has name x6". The place for the range is also redundant. It's as if "jalge" was defined as "x1 is the result of x2 among potential results x3", or something like that. "fancu" ought to have just two places: "x1 is a function of x2". Your example would be: "fy pe xy du li vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o"

Don't you think {pe} is extremely hackish here?

 

, which doesn't use "fancu", but you could also say fy fancu xy noi mrena'u gi'e zmadu li pa"

And this doesn't use the formula.

Still I think "f(x) is the name for "(x+1)(x-1)"" is a useful predicate.

 

. A more general use would be:

 

 lo jdima be lo seldi'a cu fancu lo ni sy se sabji jo'u lo ni sy se cpedu

 "The price of a good is a function of its supply and demand."

This just needs a separate brivla.

By looking at {lacri} I can see that it both means "to rely/to depend on"  and "to count on/trust".

Isn't the first pair is what is fancu (2) and the second one is something like {krici/kanpe}?

lo se vecnu cu lacri lo ni se se sabji jo'u lo ni sy se cpedu vau lo ka se jdima

Finally (3), usage, is all over the place. An example from Tatoeba (just because it's the first hit for "cu fancu" that I get from Google):

  ro da poi fancu lo nuncfa cu fancu lo nunfa'o
  Whatever is subject to origination is all subject to cessation.

But I don't really see how "fancu" can be "subject to". To me that says that every thing that depends on a start, depends on having (or being?) an end. "Being subject to" is more like "lifri". I would say: "ro da poi lifri lo ka cfari cu lifri lo ka tolcfa".

mu'o mi'e xorxes

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[Michael Turniansky]

On Thu, Nov 13, 2014 at 3:42 AM, la gleki <gleki.is...@gmail.com> wrote:

By looking at {lacri} I can see that it both means "to rely/to depend on"  and "to count on/trust".

Isn't the first pair is what is fancu (2) and the second one is something like {krici/kanpe}?

lo se vecnu cu lacri lo ni se se sabji jo'u lo ni sy se cpedu vau lo ka se jdima

  No.  They all the mean the same thing (or shades thereof):

"I know I can rely on gleki to ask questions about the gimste"

"I know I can depend on gleki  to ask questions about the gimste"

"I know I can count on gleki to ask questions about the gimste"

"I know I can trust gleki to ask questions about the gimste"

 

  Other shades of the meaning of the English word "depend" (or "rely on") could indeed be fancu in the realm of mathematics (the value of x depends on y), but less formulaic versions of dependency might be expressed by panra  (the price of bread depends on the price of wheat) or nitcu (man depends on water to live)

       --gejyspa

[Gleki Arxokuna]

2014-09-17 18:23 GMT+03:00 Jorge Llambías <jjlla...@gmail.com>:

 fy fancu lo'i mrena'u poi zmadu li pa lo'i mrena'u poi zmadu li no me'o vei xy su'i pa ve'o pi'i vei xy vu'u pa ve'o

two {vau}s needed here.