Difference between revisions of "Function Command"

Revision as of 16:47, 20 October 2011

Function[Function f, Number a, Number b]: Yields a function graph, that is equal to f on the interval [a, b] and not defined outside of [a, b].

Note:

This command should be used only to restrict the display interval of a function. To restrict the function’s domain or use it with the Sequence command, create a conditional function with the If command, e.g.
f(x) = If[-1 < x && x < 1, x²].
Example: f(x) = Function[x^2, -1, 1] produces a function equal to x² whose graph appears only in the interval [-1, 1]. However, while g(x) = 2 f(x) will produce the function g(x) = 2 x² as expected, this function is not restricted to the interval [-1, 1].

@@ Line 3: / Line 3: @@
 ; Function[Function f, Number a, Number b]: Yields a function graph, that is equal to ''f'' on the interval [''a'', ''b''] and not defined outside of [''a'', ''b''].
 {{Note|1=<div>
-* This command should be used only to restrict the display interval of a function.  To restrict the function’s domain, create a conditional function with the [[If Command|If command]], e.g. <br/><code>f(x) = If[-1 < x && x < 1, x²]</code>.
+* This command should be used only to restrict the '''display''' interval of a function.  To restrict the function’s domain or use it with the [[Sequence Command|Sequence command]], create a conditional function with the [[If Command|If command]], e.g. <br/><code>f(x) = If[-1 < x && x < 1, x²]</code>.
 * Example: <code>f(x) = Function[x^2, -1, 1]</code> produces a function equal to ''x<sup>2</sup>'' whose graph appears only in the interval [''-1'', ''1''].  However, while <code>g(x) = 2 f(x)</code> will produce the function ''g(x) = 2 x<sup>2</sup>'' as expected, this function is not restricted to the interval [''-1'', ''1''].
 </div>}}