# Manipulating a point in a StreamPlot\[ \]?

**URL:** <https://community.wolfram.com/t/manipulating-a-point-in-a-streamplot/17130>\
**Category:** Questions\
**Tags:** graphics-and-visualization, interface-construction\
**Created:** [December 3, 2020, 9:02pm UTC](https://community.wolfram.com/t/manipulating-a-point-in-a-streamplot/17130 "2020-12-03T21:02:57Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![jgourle2](https://yyz1.discourse-cdn.com/wolfram/user_avatar/community.wolfram.com/jgourle2/32/4175_2.png) [@jgourle2](https://community.wolfram.com/u/jgourle2)\
**Post date:** [December 3, 2020, 9:02pm UTC](https://community.wolfram.com/t/manipulating-a-point-in-a-streamplot/17130/1 "2020-12-03T21:02:57Z")

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I’m new to Mathematica. Why doesn’t the point in the attached expression appear where I think it should? And is there a way to attach a label to the point showing its coordinates?

[Math 413 HW 3 Prob 2 with sliders experiment and point added.nb](https://community.wolfram.com/uploads/short-url/6wgGsUxIGohjEbawUU1mj31m2Sq.nb) (10.6 KB)

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**Author:** ![rohitnamjoshi](https://avatars.discourse-cdn.com/v4/letter/r/f1d935/32.png) [@rohitnamjoshi](https://community.wolfram.com/u/rohitnamjoshi)\
**Post date:** [December 3, 2020, 10:21pm UTC](https://community.wolfram.com/t/manipulating-a-point-in-a-streamplot/17130/2 "2020-12-03T22:21:22Z")

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Hi Jay,

`Overlay` does not know anything about the scales involved. Try using `Show` instead.

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<div class="post-metadata">

**Author:** ![jgourle2](https://yyz1.discourse-cdn.com/wolfram/user_avatar/community.wolfram.com/jgourle2/32/4175_2.png) [@jgourle2](https://community.wolfram.com/u/jgourle2)\
**Post date:** [December 4, 2020, 1:21am UTC](https://community.wolfram.com/t/manipulating-a-point-in-a-streamplot/17130/3 "2020-12-04T01:21:44Z")

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Fantastic. That worked. (See attached) Thanks, Rohit Namjoshi.

Next question: Is there a way to attach a label to the point showing its coordinates? And is there a way to created a manipulatable object that can be inserted in applications like Microsoft 365, HTML email messages, or Google Docs?

[Math 413 HW 3 Prob 2 with sliders experiment and point added - Copy.nb](https://community.wolfram.com/uploads/short-url/1VrLR2lMui46BD0LS236JNeBMuG.nb) (11.3 KB)

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**Author:** ![rohitnamjoshi](https://avatars.discourse-cdn.com/v4/letter/r/f1d935/32.png) [@rohitnamjoshi](https://community.wolfram.com/u/rohitnamjoshi)\
**Post date:** [December 4, 2020, 2:32am UTC](https://community.wolfram.com/t/manipulating-a-point-in-a-streamplot/17130/4 "2020-12-04T02:32:36Z")

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This is a bit ugly, but should give you the general idea

```
Manipulate[
 p = {(1 + Subscript[\[Epsilon], 1 ])/Subscript[\[Epsilon], 
    0 ], (Subscript[\[Epsilon], 0 ] - Subscript[\[Epsilon], 1 ] - 
      1)/(Subscript[\[Epsilon], 
      0 ] (1 + Subscript[\[Epsilon], 1 ]))};
 Show[
  {
   Graphics[
    {AbsolutePointSize[5], Point[p, VertexColors -> Red], Black, 
     Text[ToString@Round[p, 0.01], {First@p, Last@p + .02}]}, 
    PlotRange -> {{dimmin, dimmax}, {dimmin, dimmax}}],
   StreamPlot[
    {1 - s - Subscript[\[Epsilon], 0 ] i s, 
     Subscript[\[Epsilon], 0 ]
        i s - (1 + Subscript[\[Epsilon], 1 ]) i}, {s, dimmin, 
     dimmax},
    {i, dimmin, dimmax}, StreamStyle -> {Automatic}, 
    StreamColorFunction -> Automatic, FrameLabel -> {s, i}, 
    StreamScale -> Automatic, ImageSize -> Full, Axes -> True, 
    AxesStyle -> Black, LabelStyle -> {13, GrayLevel[0], Bold}]
   }
  ],
 {{Subscript[\[Epsilon], 0 ], 3}, -30, 
  30, .1}, {{Subscript[\[Epsilon], 1 ], 1}, -30, 30, .1}
 ]
dimmin = 0 ; dimmax = 1.1 ;

```

The second question is very different and should be a separate post.

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<div class="post-metadata">

**Author:** ![jgourle2](https://yyz1.discourse-cdn.com/wolfram/user_avatar/community.wolfram.com/jgourle2/32/4175_2.png) [@jgourle2](https://community.wolfram.com/u/jgourle2)\
**Post date:** [December 4, 2020, 2:50am UTC](https://community.wolfram.com/t/manipulating-a-point-in-a-streamplot/17130/5 "2020-12-04T02:50:02Z")

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Thanks again, Rohit Namjoshi. That worked too. It also shows that Manipulate only manipulates variables if the variable definition is within its arguments, right?