# Graph something freehand, then it gives the function..how?

1. Aug 7, 2015

### jaysquestions

• Member warned about posting vague, unclear questions.
How or where can I do this? thanks

2. Aug 7, 2015

### Dr. Courtney

Not sure what you mean. Any recipe that gives one output for a given input can be considered a mathematical function.

For properly labeled graphs where the axes for the input and output are defined, this can be done.

3. Aug 7, 2015

### jaysquestions

I know I didn't explain it very well. This is what I mean: I draw some random curvy line and some app or software tells me the function of what I just drew. Is there some app that does this? thanks for the reply

4. Aug 7, 2015

### Staff: Mentor

The software can't tell you what the function is in all cases -- the best it can usually do is to approximate the curve (or a section of the curve) with a polynomial or other function, using some of the points on the curve.

5. Aug 7, 2015

6. Aug 7, 2015

### symbolipoint

Unclear. You must fit some numbers to what you drew, and then if expecting to use a software program, give the values to the program and run the program to produce an equation.

7. Aug 7, 2015

### symbolipoint

You are asking about the topic of Curve Fitting. One begins developing skills for this in Basic/Beginning Algebra.

8. Nov 4, 2015

### jackson.cirillo

Hello guys I'm tryng to help a student from high school to create a function from the shape of a structure, and I was thinking about drawing something like the structure and
try to find a function from it.
Does someone could give me some help?

9. Nov 4, 2015

### symbolipoint

You need good reliable values if you want to make a meaningful graph and find a reliable function or equation.