Plotting a family of functions with For

Question

I'm trying to plot a family of functions differing only by a constant $c$. The function is: $2x^2-5x+c$. In order to plot them I'm using the following code:

Plot[For[i = 0, i < 4, i++, {2 x^2 - 5 x + i}], {x, -5, 5}]

but there's no output besides the axis. The iinside the loop For is equivalent to the constant $c$ of the function. How can I plot them using the For loop inside the Plot command? Is this possible?

Look up Table. For is rarely used in Mathematica (https://mathematica.stackexchange.com/questions/134609/why-should-i-avoid-the-for-loop-in-mathematica). — Michael E2, Aug 14 '18 at 00:27
For returns Null, always. So there is nothing to plot. Do as Michael E2 instructs you. — m_goldberg, Aug 14 '18 at 00:29
The last example under "Basic Examples" in the docs for Plot shows how to do it. — Michael E2, Aug 14 '18 at 11:59

score 2 · Answer 1 · answered Aug 14 '18 at 01:25

2

Table[
 Plot[2 x^2 - 5 x + i, {x, -5, 5}], 
 {i, 0, 3}]

or if you want them all on the same axes:

Plot[
 Evaluate@Table[2 x^2 - 5 x + i, {i, 0, 3}], 
 {x, -5, 5}]

answered Aug 14 '18 at 01:25

David G. Stork

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Plotting a family of functions with For

1 Answers1