Another graphing question

[mortgageman]

My daughter is about to start the math topic of "quadratic functions". Generally speaking - for a high school class - the topic goes over formulas for symetry and shape. I wanted to put together some graphs for her. The idea would be for a function that looks like ax2+bx+c, for her to ONLY PUT IN a,b, and c. In other words just three numbers.

Now I know that if excel has two columns of numbers - the x and the y, where each y would be calculated by ax2+bx+c - it could generate the graph. I am asking if native excel can generate the graph with only the benifet of the a,b and c

Gene, "The Mortgage Man", Klein

 

[dcardno]

Look for ChtFrmla.zip at Stephen Bullen's web page. It will require that you enter the formula and a parameter for the number of points that you want to plot. You can enter the formula with references to the A,B, and C values you want to use...

 

[tusharm]

In addition to Stephen's solution, you may want to look at
Interactive graph analyzer
http://www.tushar-mehta.com/excel/software/utilities/iga.html

Essentially, it's a graphing calculator in Excel. So, your daughter can visually observe the effect of modifying the parameters.

My daughter is about to start the math topic of "quadratic functions". Generally speaking - for a high school class - the topic goes over formulas for symetry and shape. I wanted to put together some graphs for her. The idea would be for a function that looks like ax2+bx+c, for her to ONLY PUT IN a,b, and c. In other words just three numbers.

Now I know that if excel has two columns of numbers - the x and the y, where each y would be calculated by ax2+bx+c - it could generate the graph. I am asking if native excel can generate the graph with only the benifet of the a,b and c

Gene, "The Mortgage Man", Klein

 

[mortgageman]

I confess that it is not obvious (to me) how to use either of the solutions.
What I wanted (and I thought Native Excel could do it) was a way to enter just three numbers and have excel handle the rest. (The assumption being that we would only be dealing with a parabola). It sounds like Excel doesn't do that. I will see about writing it myself and let you guys and gals know how I do.

Gene, "The Mortgage Man", Klein

 

[tusharm]

{snip}I will see about writing it myself and let you guys and gals know how I do.

Gene, "The Mortgage Man", Klein

You will be reinventing the wheel. But, if that's what you want...

 

[mortgageman]

{snip}I will see about writing it myself and let you guys and gals know how I do.

Gene, "The Mortgage Man", Klein

You will be reinventing the wheel. But, if that's what you want...

What am I missing? The two solutions presented here were not (at least as far as I can tell) of the form where I could just enter a, b and c.

Gene, "The Mortgage Man", Klein

 

[tusharm]

Did you download Stephen's workbook? It is, by and large, self-explanatory.

As was, I thought, my add-in. But, maybe, not.

Install and load the add-in.

In an otherwise empty worksheet, in A1:A5 enter the literals a,b,c,x, and y respectively.

Select A1:B5 then Insert | Name > Create... In the resulting dialog box ensure only 'Left Column' is checked.

In B5 enter =a*x^2+b*x+c_

Select TM | Charts > Interactive graph analyzer...

In 'Plot what cell' specify B5. In the 'vs. what cell' specify B4.

Set the min. value to -5, the max. value to 5, the number of points to 20. You can experiment with these later.

Click Update. Now, in the lower half of the userform, experiment with different values of a, b, and c. Either enter numbers in the appropriate textboxes or use the scrollers to change the values.

{snip}

What am I missing? The two solutions presented here were not (at least as far as I can tell) of the form where I could just enter a, b and c.

Gene, "The Mortgage Man", Klein

 

[mortgageman]

Wow Tusharm, I gotta tell you, I NEVER, EVER would have figured that out on my own. I just tried it and it worked, but then I made it bomb out. (You know what they say about making things idiot proof)

I try some more tommorow - (I'm also 1/2 way done writing my own)

Gene, "The Mortgage Man", Klein