Function Repository Resource:

IsContinuousFunction

Source Notebook

Determine whether a function is continuous

Contributed by: Wolfram|Alpha Math Team

ResourceFunction["IsContinuousFunction"][expr,x,pt]

assesses whether expr is continuous, viewed as a real-valued function of x, at the point x=pt.

ResourceFunction["IsContinuousFunction"][expr,x]

assesses whether expr is continuous over the full set of real numbers.

ResourceFunction["IsContinuousFunction"][{expr,cond},x]

assesses whether expr is continuous, subject to condition cond.

Details and Options

A function is continuous at a point c if . The function f is continuous on if it is continuous at every point .

Examples

Basic Examples (2) 

Test if a function is continuous over the Reals:

In[1]:=
ResourceFunction[
 "IsContinuousFunction", ResourceSystemBase -> "https://www.wolframcloud.com/obj/resourcesystem/api/1.0"][Sin[x], x]
Out[1]=

Test if a function is continuous at a point:

In[2]:=
ResourceFunction[
 "IsContinuousFunction", ResourceSystemBase -> "https://www.wolframcloud.com/obj/resourcesystem/api/1.0"][Tan[x], x, Pi]
Out[2]=
In[3]:=
ResourceFunction[
 "IsContinuousFunction", ResourceSystemBase -> "https://www.wolframcloud.com/obj/resourcesystem/api/1.0"][Tan[x], x, Pi/2]
Out[3]=

Scope (2) 

One can explicitly specify a domain over which to test continuity:

In[4]:=
ResourceFunction[
 "IsContinuousFunction", ResourceSystemBase -> "https://www.wolframcloud.com/obj/resourcesystem/api/1.0"][{1/x, x != 0}, x]
Out[4]=

Omitting the condition on x produces a different result:

In[5]:=
ResourceFunction[
 "IsContinuousFunction", ResourceSystemBase -> "https://www.wolframcloud.com/obj/resourcesystem/api/1.0"][1/x, x]
Out[5]=

Properties and Relations (1) 

IsContinuousFunction uses the resource function FunctionDiscontinuities to determine the points of discontinuity of an expression:

In[6]:=
ResourceFunction["FunctionDiscontinuities"][1/x, x]
Out[6]=

Publisher

Wolfram|Alpha Math Team

Version History

  • 3.0.0 – 23 March 2023
  • 2.0.0 – 23 July 2020
  • 1.0.0 – 23 July 2020

Related Resources

Author Notes

To view underlying paclet code, evaluate the following:

In[1]:=
SystemOpen[
 FileNameJoin[
  ReplacePart[
   FileNameSplit[FindFile["ResourceFunctionHelpers`"]], -1 -> "IsContinuousFunction.wl"]]]

License Information