What is a smooth surface?











up vote
1
down vote

favorite












What is a smooth surface in terms of tangents and normals?
I read in a book that surfaces are smooth if its surface normals depend continuously on the points of that surface.
I did not understand this definition, could somebody simplify it for me?










share|cite|improve this question
























  • the surface normal is a vector-function!
    – W_D
    Jul 21 '13 at 19:27






  • 1




    so what is a smooth surface ?
    – sagar
    Jul 21 '13 at 19:29










  • The unit normal is a smooth vector function of the coordinate of the point on the surface so $n=(n_x,n_y,n_z)$ is a smooth function of $(x,y,z)$ that satisfies the equation of surface. A surface is generally parametrized through two variables, e.g., $r=(u,v)$, so you want $n$ to be a smooth function of $r$. The smooth typically means twice continuously differentiable.
    – Maesumi
    Jul 21 '13 at 19:57










  • Here is another way: hold a pencil perpendicular to an apple! Most of the time as you move the base of the point around the pen just moves smoothly with the base, but if you try to go through where the stems used to be the pencil goes through some jerky movements, at that point the surface of apple is not smooth!
    – Maesumi
    Jul 21 '13 at 20:00






  • 1




    so when ever there is a sharp in the graph or a discontinuity where the normal does not exist , then the surface no longer remains smooth ? ! Did i get it right ?
    – sagar
    Jul 21 '13 at 21:29















up vote
1
down vote

favorite












What is a smooth surface in terms of tangents and normals?
I read in a book that surfaces are smooth if its surface normals depend continuously on the points of that surface.
I did not understand this definition, could somebody simplify it for me?










share|cite|improve this question
























  • the surface normal is a vector-function!
    – W_D
    Jul 21 '13 at 19:27






  • 1




    so what is a smooth surface ?
    – sagar
    Jul 21 '13 at 19:29










  • The unit normal is a smooth vector function of the coordinate of the point on the surface so $n=(n_x,n_y,n_z)$ is a smooth function of $(x,y,z)$ that satisfies the equation of surface. A surface is generally parametrized through two variables, e.g., $r=(u,v)$, so you want $n$ to be a smooth function of $r$. The smooth typically means twice continuously differentiable.
    – Maesumi
    Jul 21 '13 at 19:57










  • Here is another way: hold a pencil perpendicular to an apple! Most of the time as you move the base of the point around the pen just moves smoothly with the base, but if you try to go through where the stems used to be the pencil goes through some jerky movements, at that point the surface of apple is not smooth!
    – Maesumi
    Jul 21 '13 at 20:00






  • 1




    so when ever there is a sharp in the graph or a discontinuity where the normal does not exist , then the surface no longer remains smooth ? ! Did i get it right ?
    – sagar
    Jul 21 '13 at 21:29













up vote
1
down vote

favorite









up vote
1
down vote

favorite











What is a smooth surface in terms of tangents and normals?
I read in a book that surfaces are smooth if its surface normals depend continuously on the points of that surface.
I did not understand this definition, could somebody simplify it for me?










share|cite|improve this question















What is a smooth surface in terms of tangents and normals?
I read in a book that surfaces are smooth if its surface normals depend continuously on the points of that surface.
I did not understand this definition, could somebody simplify it for me?







multivariable-calculus surfaces






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Feb 19 '14 at 11:38









Maroon

287313




287313










asked Jul 21 '13 at 19:25









sagar

1112




1112












  • the surface normal is a vector-function!
    – W_D
    Jul 21 '13 at 19:27






  • 1




    so what is a smooth surface ?
    – sagar
    Jul 21 '13 at 19:29










  • The unit normal is a smooth vector function of the coordinate of the point on the surface so $n=(n_x,n_y,n_z)$ is a smooth function of $(x,y,z)$ that satisfies the equation of surface. A surface is generally parametrized through two variables, e.g., $r=(u,v)$, so you want $n$ to be a smooth function of $r$. The smooth typically means twice continuously differentiable.
    – Maesumi
    Jul 21 '13 at 19:57










  • Here is another way: hold a pencil perpendicular to an apple! Most of the time as you move the base of the point around the pen just moves smoothly with the base, but if you try to go through where the stems used to be the pencil goes through some jerky movements, at that point the surface of apple is not smooth!
    – Maesumi
    Jul 21 '13 at 20:00






  • 1




    so when ever there is a sharp in the graph or a discontinuity where the normal does not exist , then the surface no longer remains smooth ? ! Did i get it right ?
    – sagar
    Jul 21 '13 at 21:29


















  • the surface normal is a vector-function!
    – W_D
    Jul 21 '13 at 19:27






  • 1




    so what is a smooth surface ?
    – sagar
    Jul 21 '13 at 19:29










  • The unit normal is a smooth vector function of the coordinate of the point on the surface so $n=(n_x,n_y,n_z)$ is a smooth function of $(x,y,z)$ that satisfies the equation of surface. A surface is generally parametrized through two variables, e.g., $r=(u,v)$, so you want $n$ to be a smooth function of $r$. The smooth typically means twice continuously differentiable.
    – Maesumi
    Jul 21 '13 at 19:57










  • Here is another way: hold a pencil perpendicular to an apple! Most of the time as you move the base of the point around the pen just moves smoothly with the base, but if you try to go through where the stems used to be the pencil goes through some jerky movements, at that point the surface of apple is not smooth!
    – Maesumi
    Jul 21 '13 at 20:00






  • 1




    so when ever there is a sharp in the graph or a discontinuity where the normal does not exist , then the surface no longer remains smooth ? ! Did i get it right ?
    – sagar
    Jul 21 '13 at 21:29
















the surface normal is a vector-function!
– W_D
Jul 21 '13 at 19:27




the surface normal is a vector-function!
– W_D
Jul 21 '13 at 19:27




1




1




so what is a smooth surface ?
– sagar
Jul 21 '13 at 19:29




so what is a smooth surface ?
– sagar
Jul 21 '13 at 19:29












The unit normal is a smooth vector function of the coordinate of the point on the surface so $n=(n_x,n_y,n_z)$ is a smooth function of $(x,y,z)$ that satisfies the equation of surface. A surface is generally parametrized through two variables, e.g., $r=(u,v)$, so you want $n$ to be a smooth function of $r$. The smooth typically means twice continuously differentiable.
– Maesumi
Jul 21 '13 at 19:57




The unit normal is a smooth vector function of the coordinate of the point on the surface so $n=(n_x,n_y,n_z)$ is a smooth function of $(x,y,z)$ that satisfies the equation of surface. A surface is generally parametrized through two variables, e.g., $r=(u,v)$, so you want $n$ to be a smooth function of $r$. The smooth typically means twice continuously differentiable.
– Maesumi
Jul 21 '13 at 19:57












Here is another way: hold a pencil perpendicular to an apple! Most of the time as you move the base of the point around the pen just moves smoothly with the base, but if you try to go through where the stems used to be the pencil goes through some jerky movements, at that point the surface of apple is not smooth!
– Maesumi
Jul 21 '13 at 20:00




Here is another way: hold a pencil perpendicular to an apple! Most of the time as you move the base of the point around the pen just moves smoothly with the base, but if you try to go through where the stems used to be the pencil goes through some jerky movements, at that point the surface of apple is not smooth!
– Maesumi
Jul 21 '13 at 20:00




1




1




so when ever there is a sharp in the graph or a discontinuity where the normal does not exist , then the surface no longer remains smooth ? ! Did i get it right ?
– sagar
Jul 21 '13 at 21:29




so when ever there is a sharp in the graph or a discontinuity where the normal does not exist , then the surface no longer remains smooth ? ! Did i get it right ?
– sagar
Jul 21 '13 at 21:29










4 Answers
4






active

oldest

votes

















up vote
3
down vote













if you have a surface (in $mathbb{R}^3$). it can be given by $x = x(u,v), y = y(u,v), z = z(u,v)$, where $u$ and $v$ are parameters from a subset $Asubset mathbb{R}^2$. So $r(u,v) = (x(u,v),y(u,v),z(u,v))$ is a map from $A$ into $mathbb{R}^3$. Whenever you fix any parameter, say, $u$, you'll obtain a curve on your surface, so, if it is possible (if these functions are differentiable) you can define tangent vertors $r_v$, $r_u$ (they are partial derivatives of $r$ with respect to respective parameters) for these curves. In some good cases these two vectors will not be parallel and thus will form the base of a tangent plane (but it doesn't always exist, consider the top of a cone) to your surface at any given point $(u,v)$. Then you can calculate the normal vector of unit length at any point $(u,v)$ by computing the cross product of $r_v$ and $r_u$ and dividing it by its length. In this way you'll obtain a function $n(u,v)$, it must be continuous... Sorry for being that unclear...






share|cite|improve this answer





















  • The issue at the "top of a cone" is a discontinuity in the derivative. Also, you are considering a very narrow case, and some of the details are irrelevant.
    – pre-kidney
    Jul 21 '13 at 20:57


















up vote
1
down vote













"Smooth" just means that all the functions involved in the description of the object have infinitely many derivatives. In other words, they are continuous, differentiable, and so on for each derivative.



For instance, if your surface is described by polynomials, then it is smooth.



Note: To avoid confusion, when I say polynomial I mean polynomial, not "piecewise polynomial".






share|cite|improve this answer























  • You may wanna add that the polynomials shouldn't be a piecewisely defined one.
    – Shuhao Cao
    Jul 21 '13 at 21:13










  • It seemed clear to me that "polynomial" doesn't mean "piecewise polynomial", but I guess it doesn't hurt to add this clarification.
    – pre-kidney
    Jul 21 '13 at 21:16










  • thanks a lot ! :) . I got it !
    – sagar
    Jul 21 '13 at 21:30


















up vote
0
down vote













A surface is a 2D subset of 3D. "IS" means there is a local homeomorphism (1 to 1 onto invertable relation) between 2D and the surface. Smoothnes is the continuity of this defining homeomorphism. If it is differentiable, the surface is SMOOTH or G1. G2 surfaces are aerodynamically desirable.






share|cite|improve this answer




























    up vote
    0
    down vote













    Take an example of sphere. Now each and every point on sphere has a unique normal vector. That's why the surface of sphere is called smooth surface.






    share|cite|improve this answer





















      Your Answer





      StackExchange.ifUsing("editor", function () {
      return StackExchange.using("mathjaxEditing", function () {
      StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
      StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
      });
      });
      }, "mathjax-editing");

      StackExchange.ready(function() {
      var channelOptions = {
      tags: "".split(" "),
      id: "69"
      };
      initTagRenderer("".split(" "), "".split(" "), channelOptions);

      StackExchange.using("externalEditor", function() {
      // Have to fire editor after snippets, if snippets enabled
      if (StackExchange.settings.snippets.snippetsEnabled) {
      StackExchange.using("snippets", function() {
      createEditor();
      });
      }
      else {
      createEditor();
      }
      });

      function createEditor() {
      StackExchange.prepareEditor({
      heartbeatType: 'answer',
      convertImagesToLinks: true,
      noModals: true,
      showLowRepImageUploadWarning: true,
      reputationToPostImages: 10,
      bindNavPrevention: true,
      postfix: "",
      imageUploader: {
      brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
      contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
      allowUrls: true
      },
      noCode: true, onDemand: true,
      discardSelector: ".discard-answer"
      ,immediatelyShowMarkdownHelp:true
      });


      }
      });














      draft saved

      draft discarded


















      StackExchange.ready(
      function () {
      StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f448979%2fwhat-is-a-smooth-surface%23new-answer', 'question_page');
      }
      );

      Post as a guest















      Required, but never shown

























      4 Answers
      4






      active

      oldest

      votes








      4 Answers
      4






      active

      oldest

      votes









      active

      oldest

      votes






      active

      oldest

      votes








      up vote
      3
      down vote













      if you have a surface (in $mathbb{R}^3$). it can be given by $x = x(u,v), y = y(u,v), z = z(u,v)$, where $u$ and $v$ are parameters from a subset $Asubset mathbb{R}^2$. So $r(u,v) = (x(u,v),y(u,v),z(u,v))$ is a map from $A$ into $mathbb{R}^3$. Whenever you fix any parameter, say, $u$, you'll obtain a curve on your surface, so, if it is possible (if these functions are differentiable) you can define tangent vertors $r_v$, $r_u$ (they are partial derivatives of $r$ with respect to respective parameters) for these curves. In some good cases these two vectors will not be parallel and thus will form the base of a tangent plane (but it doesn't always exist, consider the top of a cone) to your surface at any given point $(u,v)$. Then you can calculate the normal vector of unit length at any point $(u,v)$ by computing the cross product of $r_v$ and $r_u$ and dividing it by its length. In this way you'll obtain a function $n(u,v)$, it must be continuous... Sorry for being that unclear...






      share|cite|improve this answer





















      • The issue at the "top of a cone" is a discontinuity in the derivative. Also, you are considering a very narrow case, and some of the details are irrelevant.
        – pre-kidney
        Jul 21 '13 at 20:57















      up vote
      3
      down vote













      if you have a surface (in $mathbb{R}^3$). it can be given by $x = x(u,v), y = y(u,v), z = z(u,v)$, where $u$ and $v$ are parameters from a subset $Asubset mathbb{R}^2$. So $r(u,v) = (x(u,v),y(u,v),z(u,v))$ is a map from $A$ into $mathbb{R}^3$. Whenever you fix any parameter, say, $u$, you'll obtain a curve on your surface, so, if it is possible (if these functions are differentiable) you can define tangent vertors $r_v$, $r_u$ (they are partial derivatives of $r$ with respect to respective parameters) for these curves. In some good cases these two vectors will not be parallel and thus will form the base of a tangent plane (but it doesn't always exist, consider the top of a cone) to your surface at any given point $(u,v)$. Then you can calculate the normal vector of unit length at any point $(u,v)$ by computing the cross product of $r_v$ and $r_u$ and dividing it by its length. In this way you'll obtain a function $n(u,v)$, it must be continuous... Sorry for being that unclear...






      share|cite|improve this answer





















      • The issue at the "top of a cone" is a discontinuity in the derivative. Also, you are considering a very narrow case, and some of the details are irrelevant.
        – pre-kidney
        Jul 21 '13 at 20:57













      up vote
      3
      down vote










      up vote
      3
      down vote









      if you have a surface (in $mathbb{R}^3$). it can be given by $x = x(u,v), y = y(u,v), z = z(u,v)$, where $u$ and $v$ are parameters from a subset $Asubset mathbb{R}^2$. So $r(u,v) = (x(u,v),y(u,v),z(u,v))$ is a map from $A$ into $mathbb{R}^3$. Whenever you fix any parameter, say, $u$, you'll obtain a curve on your surface, so, if it is possible (if these functions are differentiable) you can define tangent vertors $r_v$, $r_u$ (they are partial derivatives of $r$ with respect to respective parameters) for these curves. In some good cases these two vectors will not be parallel and thus will form the base of a tangent plane (but it doesn't always exist, consider the top of a cone) to your surface at any given point $(u,v)$. Then you can calculate the normal vector of unit length at any point $(u,v)$ by computing the cross product of $r_v$ and $r_u$ and dividing it by its length. In this way you'll obtain a function $n(u,v)$, it must be continuous... Sorry for being that unclear...






      share|cite|improve this answer












      if you have a surface (in $mathbb{R}^3$). it can be given by $x = x(u,v), y = y(u,v), z = z(u,v)$, where $u$ and $v$ are parameters from a subset $Asubset mathbb{R}^2$. So $r(u,v) = (x(u,v),y(u,v),z(u,v))$ is a map from $A$ into $mathbb{R}^3$. Whenever you fix any parameter, say, $u$, you'll obtain a curve on your surface, so, if it is possible (if these functions are differentiable) you can define tangent vertors $r_v$, $r_u$ (they are partial derivatives of $r$ with respect to respective parameters) for these curves. In some good cases these two vectors will not be parallel and thus will form the base of a tangent plane (but it doesn't always exist, consider the top of a cone) to your surface at any given point $(u,v)$. Then you can calculate the normal vector of unit length at any point $(u,v)$ by computing the cross product of $r_v$ and $r_u$ and dividing it by its length. In this way you'll obtain a function $n(u,v)$, it must be continuous... Sorry for being that unclear...







      share|cite|improve this answer












      share|cite|improve this answer



      share|cite|improve this answer










      answered Jul 21 '13 at 19:59









      W_D

      4571310




      4571310












      • The issue at the "top of a cone" is a discontinuity in the derivative. Also, you are considering a very narrow case, and some of the details are irrelevant.
        – pre-kidney
        Jul 21 '13 at 20:57


















      • The issue at the "top of a cone" is a discontinuity in the derivative. Also, you are considering a very narrow case, and some of the details are irrelevant.
        – pre-kidney
        Jul 21 '13 at 20:57
















      The issue at the "top of a cone" is a discontinuity in the derivative. Also, you are considering a very narrow case, and some of the details are irrelevant.
      – pre-kidney
      Jul 21 '13 at 20:57




      The issue at the "top of a cone" is a discontinuity in the derivative. Also, you are considering a very narrow case, and some of the details are irrelevant.
      – pre-kidney
      Jul 21 '13 at 20:57










      up vote
      1
      down vote













      "Smooth" just means that all the functions involved in the description of the object have infinitely many derivatives. In other words, they are continuous, differentiable, and so on for each derivative.



      For instance, if your surface is described by polynomials, then it is smooth.



      Note: To avoid confusion, when I say polynomial I mean polynomial, not "piecewise polynomial".






      share|cite|improve this answer























      • You may wanna add that the polynomials shouldn't be a piecewisely defined one.
        – Shuhao Cao
        Jul 21 '13 at 21:13










      • It seemed clear to me that "polynomial" doesn't mean "piecewise polynomial", but I guess it doesn't hurt to add this clarification.
        – pre-kidney
        Jul 21 '13 at 21:16










      • thanks a lot ! :) . I got it !
        – sagar
        Jul 21 '13 at 21:30















      up vote
      1
      down vote













      "Smooth" just means that all the functions involved in the description of the object have infinitely many derivatives. In other words, they are continuous, differentiable, and so on for each derivative.



      For instance, if your surface is described by polynomials, then it is smooth.



      Note: To avoid confusion, when I say polynomial I mean polynomial, not "piecewise polynomial".






      share|cite|improve this answer























      • You may wanna add that the polynomials shouldn't be a piecewisely defined one.
        – Shuhao Cao
        Jul 21 '13 at 21:13










      • It seemed clear to me that "polynomial" doesn't mean "piecewise polynomial", but I guess it doesn't hurt to add this clarification.
        – pre-kidney
        Jul 21 '13 at 21:16










      • thanks a lot ! :) . I got it !
        – sagar
        Jul 21 '13 at 21:30













      up vote
      1
      down vote










      up vote
      1
      down vote









      "Smooth" just means that all the functions involved in the description of the object have infinitely many derivatives. In other words, they are continuous, differentiable, and so on for each derivative.



      For instance, if your surface is described by polynomials, then it is smooth.



      Note: To avoid confusion, when I say polynomial I mean polynomial, not "piecewise polynomial".






      share|cite|improve this answer














      "Smooth" just means that all the functions involved in the description of the object have infinitely many derivatives. In other words, they are continuous, differentiable, and so on for each derivative.



      For instance, if your surface is described by polynomials, then it is smooth.



      Note: To avoid confusion, when I say polynomial I mean polynomial, not "piecewise polynomial".







      share|cite|improve this answer














      share|cite|improve this answer



      share|cite|improve this answer








      edited Jul 21 '13 at 21:17

























      answered Jul 21 '13 at 20:53









      pre-kidney

      12.6k1746




      12.6k1746












      • You may wanna add that the polynomials shouldn't be a piecewisely defined one.
        – Shuhao Cao
        Jul 21 '13 at 21:13










      • It seemed clear to me that "polynomial" doesn't mean "piecewise polynomial", but I guess it doesn't hurt to add this clarification.
        – pre-kidney
        Jul 21 '13 at 21:16










      • thanks a lot ! :) . I got it !
        – sagar
        Jul 21 '13 at 21:30


















      • You may wanna add that the polynomials shouldn't be a piecewisely defined one.
        – Shuhao Cao
        Jul 21 '13 at 21:13










      • It seemed clear to me that "polynomial" doesn't mean "piecewise polynomial", but I guess it doesn't hurt to add this clarification.
        – pre-kidney
        Jul 21 '13 at 21:16










      • thanks a lot ! :) . I got it !
        – sagar
        Jul 21 '13 at 21:30
















      You may wanna add that the polynomials shouldn't be a piecewisely defined one.
      – Shuhao Cao
      Jul 21 '13 at 21:13




      You may wanna add that the polynomials shouldn't be a piecewisely defined one.
      – Shuhao Cao
      Jul 21 '13 at 21:13












      It seemed clear to me that "polynomial" doesn't mean "piecewise polynomial", but I guess it doesn't hurt to add this clarification.
      – pre-kidney
      Jul 21 '13 at 21:16




      It seemed clear to me that "polynomial" doesn't mean "piecewise polynomial", but I guess it doesn't hurt to add this clarification.
      – pre-kidney
      Jul 21 '13 at 21:16












      thanks a lot ! :) . I got it !
      – sagar
      Jul 21 '13 at 21:30




      thanks a lot ! :) . I got it !
      – sagar
      Jul 21 '13 at 21:30










      up vote
      0
      down vote













      A surface is a 2D subset of 3D. "IS" means there is a local homeomorphism (1 to 1 onto invertable relation) between 2D and the surface. Smoothnes is the continuity of this defining homeomorphism. If it is differentiable, the surface is SMOOTH or G1. G2 surfaces are aerodynamically desirable.






      share|cite|improve this answer

























        up vote
        0
        down vote













        A surface is a 2D subset of 3D. "IS" means there is a local homeomorphism (1 to 1 onto invertable relation) between 2D and the surface. Smoothnes is the continuity of this defining homeomorphism. If it is differentiable, the surface is SMOOTH or G1. G2 surfaces are aerodynamically desirable.






        share|cite|improve this answer























          up vote
          0
          down vote










          up vote
          0
          down vote









          A surface is a 2D subset of 3D. "IS" means there is a local homeomorphism (1 to 1 onto invertable relation) between 2D and the surface. Smoothnes is the continuity of this defining homeomorphism. If it is differentiable, the surface is SMOOTH or G1. G2 surfaces are aerodynamically desirable.






          share|cite|improve this answer












          A surface is a 2D subset of 3D. "IS" means there is a local homeomorphism (1 to 1 onto invertable relation) between 2D and the surface. Smoothnes is the continuity of this defining homeomorphism. If it is differentiable, the surface is SMOOTH or G1. G2 surfaces are aerodynamically desirable.







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered Mar 22 '15 at 19:25









          Frank Ford Little Ph.D.

          1




          1






















              up vote
              0
              down vote













              Take an example of sphere. Now each and every point on sphere has a unique normal vector. That's why the surface of sphere is called smooth surface.






              share|cite|improve this answer

























                up vote
                0
                down vote













                Take an example of sphere. Now each and every point on sphere has a unique normal vector. That's why the surface of sphere is called smooth surface.






                share|cite|improve this answer























                  up vote
                  0
                  down vote










                  up vote
                  0
                  down vote









                  Take an example of sphere. Now each and every point on sphere has a unique normal vector. That's why the surface of sphere is called smooth surface.






                  share|cite|improve this answer












                  Take an example of sphere. Now each and every point on sphere has a unique normal vector. That's why the surface of sphere is called smooth surface.







                  share|cite|improve this answer












                  share|cite|improve this answer



                  share|cite|improve this answer










                  answered Nov 17 at 17:29









                  user616873

                  1




                  1






























                      draft saved

                      draft discarded




















































                      Thanks for contributing an answer to Mathematics Stack Exchange!


                      • Please be sure to answer the question. Provide details and share your research!

                      But avoid



                      • Asking for help, clarification, or responding to other answers.

                      • Making statements based on opinion; back them up with references or personal experience.


                      Use MathJax to format equations. MathJax reference.


                      To learn more, see our tips on writing great answers.





                      Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


                      Please pay close attention to the following guidance:


                      • Please be sure to answer the question. Provide details and share your research!

                      But avoid



                      • Asking for help, clarification, or responding to other answers.

                      • Making statements based on opinion; back them up with references or personal experience.


                      To learn more, see our tips on writing great answers.




                      draft saved


                      draft discarded














                      StackExchange.ready(
                      function () {
                      StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f448979%2fwhat-is-a-smooth-surface%23new-answer', 'question_page');
                      }
                      );

                      Post as a guest















                      Required, but never shown





















































                      Required, but never shown














                      Required, but never shown












                      Required, but never shown







                      Required, but never shown

































                      Required, but never shown














                      Required, but never shown












                      Required, but never shown







                      Required, but never shown







                      Popular posts from this blog

                      AnyDesk - Fatal Program Failure

                      How to calibrate 16:9 built-in touch-screen to a 4:3 resolution?

                      QoS: MAC-Priority for clients behind a repeater