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Advanced Graphing "Go To" - Printable Version

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Advanced Graphing "Go To" - swisscow - 06-09-2014 12:28 PM

Hi all

Could someone explain how the "Go To" works in advanced graphing - plot view. For example, if I have V1: y=2x+1, the plot is a straight line as expected. Then if I choose "go to", boxes to put in X and Y come up. Am I supposed to choose one, or type them both in so that the values are on the line (e.g. x=1, y=5)? I'm hoping that it's like the Casio in which one can type in the y-value and then it jumps to the x-value but I really don't know what's going on.

Many thanks


RE: Advanced Graphing "Go To" - Tim Wessman - 06-09-2014 02:12 PM

Hello,

Remember that the adv grapher can graph stuff not normally possible on any other graphing calculator. As part of this, you can position the cursor in any X or Y location as regions/edges etc are all valid. Where the confusion is probably coming in is that the cursor will automatically reposition itself onto the curve (or edge, or region) *closest* to the location entered since by default TRACE is turned on. So for example, if you are graphing Y=SIN(X) (radians) and type 5 for X and 10 for Y, you actually will end up around 7.5X and .96 Y.

If you are graphing a plain function, they normal function app is probably a better choice as it is tuned for that purpose. In there, just begin typing a number and you get a single box for a single X location. That is more exactly what you seem to be looking for.


RE: Advanced Graphing "Go To" - CR Haeger - 06-09-2014 02:21 PM

Hi,

It looks to me like if you enter X: and Y: in their respective cells, the Prime will look for the "closest valid" point to that x,y coordinate. A valid point seems to be determined by both the equation(s)/inequality(s) you enter and the Menu>Trace settings you choose as well.

It may be useful to do this using the Num view and edit X and Y cells directly there. This shows you where the point of interest and surrounding points are valid (=true).


RE: Advanced Graphing "Go To" - swisscow - 06-09-2014 02:26 PM

(06-09-2014 02:12 PM)Tim Wessman Wrote:  Hello,

Remember that the adv grapher can graph stuff not normally possible on any other graphing calculator. As part of this, you can position the cursor in any X or Y location as regions/edges etc are all valid. Where the confusion is probably coming in is that the cursor will automatically reposition itself onto the curve (or edge, or region) *closest* to the location entered since by default TRACE is turned on. So for example, if you are graphing Y=SIN(X) (radians) and type 5 for X and 10 for Y, you actually will end up around 7.5X and .96 Y.

If you are graphing a plain function, they normal function app is probably a better choice as it is tuned for that purpose. In there, just begin typing a number and you get a single box for a single X location. That is more exactly what you seem to be looking for.

Hi Tim,

Thanks for your answer. So just to be clear, the "go to" in he advanced graphing puts the cursor as near as possible to the coordinates typed in. Just two questions:

1) out of interest, how does the calculator decide where is the nearest point (Pythagoras?)?

2) Is it possible in any of the graphing apps to type in the y-coordinate / value of the function and be given the x value in return?

Many thanks Tim and anyone else who wants to chip in.


RE: Advanced Graphing "Go To" - Tim Wessman - 06-09-2014 02:47 PM

(06-09-2014 02:26 PM)swisscow Wrote:  1) out of interest, how does the calculator decide where is the nearest point (Pythagoras?)?

Not sure as I didn't write this part. I would assume that or a faster variant of it however.

Quote:2) Is it possible in any of the graphing apps to type in the y-coordinate / value of the function and be given the x value in return?

Of course. What you are looking for is in the NUM view of the adv grapher. With my example of Y=SIN(X), go to the NUM view and press the TRACE button. Ensure that "Edge" is checked. You will see the table change to Y followed by multiple X columns. Pressing X down on the menu toggles to X, then Y to go back to Y and so on.

With the table selected in the Y column, type your value. If there are multiple on screen, they will all show up in the columns. Note that the table view is linked to the plot view so if you aren't showing anything on screen it won't have any values here. You can do this with horizontal extrema, inflection points, intercepts, etc.


RE: Advanced Graphing "Go To" - swisscow - 06-09-2014 03:16 PM

Great stuff!

Thanks Tim