Questions on position tracking, especially using Mathematica coordinate tracking functions and control objects such as Locator, LocatorPane, and ClickPane.

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2
votes
2answers
63 views

How-to let user define a set of VertexCoordinates in a Graph

Here is a simple code I wrote to visualize what I am trying to achieve: C.1 ...
3
votes
2answers
77 views

Manipulate a 2D point controlled simultaneously by Locator and its coordinates

I'm trying to have a point in the plane which can be manipulated both using Locator as well as inserting its $x$ and $y$ coordinates. My attempts at doing this are: ...
2
votes
2answers
104 views

How to restrict the motion of a Manipulate-generated Locator along a line?

If one uses a stand-alone locator and needs it to only be movable along a curve, say, defined by a function f[x], one can use a simple construct: ...
2
votes
1answer
125 views

How do I constrain movement for lists of Locators using 2nd argument of Dynamic?

I need to display edge labels of a graph in a way that allows the edge labels to be moved. Locator seems the simplest and most obvious function to use. My ...
5
votes
2answers
84 views

Locator-based abscissa ranges widget

I'm trying to implement a widget that will enable users to graphically determine certain abscissa ranges in a 2D plot. I've started by coding a prototype, whose output looks like this: The idea ...
0
votes
0answers
41 views

Dynamic locator missing when image change

I plan to get corner coordinate of desired image dynamically through LocatorPane[Dynamic[pt],back]. However, I notice that locator on right hand side was ...
2
votes
2answers
90 views

Locator and manipulate

How can I achieve that the points on a Graphics element could be manipulated both by Locators (clicking and moving) and on the Manipulate panel as well. As you can see, only one of the methods work. ...
0
votes
1answer
62 views

Interacting Dynamic Components within LocatorPane

I am attempting to create a dynamic contour plot of an ellipse with two locators as the foci within a locator pane. The following code has been implemented: ...
2
votes
2answers
103 views

How to do dynamic range selection for data fitting in Log plot?

In linear plot, this can be achived by Locator like this: http://mathematica.stackexchange.com/a/24935/13580 ...
1
vote
1answer
115 views

Locator with Integer value coordinates [duplicate]

I want to get the Pixel value of an image.and here is my code ...
0
votes
2answers
117 views

How to fit points in a picture using locators

I've got a problem doing some analysis work on some of my spectra. I am basically looking for features that look like parabolas. In need of a tool to quickly find two parabolas in a spectrum (they are ...
2
votes
1answer
41 views

Disable locator-removal in LocatorPane

is there a way to DISABLE the ability to remove points with ALT-click (APPLE-click) from a locator pane? I'm writing a code that allows users to manually label objects in an image by connecting two ...
1
vote
2answers
86 views

Manipulate with Locator question

Here is an example from Mathematica's help: Manipulate[Graphics[Polygon[pt], PlotRange -> 2], {{pt, {{0, 0}, {1, 0}, {1, 1}, {0, 1}, {1, -1}}}, Locator}] ...
1
vote
2answers
128 views

Enabling/disabling individual locators within a Manipulate

This post helped me out somewhat but it is missing a piece that I really need for something that I am working on that's more complex than what I've shown below. I want to disable a ...
3
votes
4answers
186 views

EventHandler Not Detecting KeyDown

I am trying to use EventHandler to detect KeyDown within a LocatorPane. Anytime I press a key inside the LocatorPane the proper action is not executed (doesn't matter which key I choose) but rather ...
1
vote
1answer
91 views

Attaching functions to movable locators

I'm trying to create a manipulate plot showing the electric field due to a collection of point charges. At the moment I've created such a plot which allows the x and y positions of each charge to be ...
4
votes
3answers
513 views

Constrain movement of a locator inside Manipulate

Once again a big thank you for the great help in my earlier post: Plotting function with Dynamic parameter. It totally worked out. I now have a new coding problem ...
4
votes
2answers
164 views

Layers of Locators of Different Colors?

I am a Mathematica novice trying to do some interactive segmentation of microscopy images. I've been trying to understand and build upon some code from a previous StackExchange discussion (Can ...
6
votes
3answers
187 views

Circumnavigating a curve or going through it to show different behavior

I am not sure if what I want to do is possible in Mathematica. I've provided something simple below to convey what I want to do. Basically what I want to happen is that when the ...
6
votes
1answer
173 views

Different actions with dragging and clicking points in same graphic

On a graphic (in this example a simple plot), I need two points to move when I drag with the mouse, and these points must move to location {1,1} when I click on them. This is how I got it to work, ...
0
votes
1answer
135 views

Using a LocatorPane

I have a network of a power grid where the edge are the power lines and the vertices are loads or generators. I was wondering how I can import an image into Mathematica to derive some sort of ...
3
votes
1answer
104 views

Export LocatorPane as image by button

How to Export LocatorPane as image by button or at least by something else? Kuba, thank you! Your method works in a simple case: ...
4
votes
2answers
173 views

Clicking to add/remove a Locator

I would like to add a Locator to a figure displayed by Manipulate when I click inside the figure, at the location where I click, ...
1
vote
0answers
84 views

How do I keep a random value associated with a locator point as points are added?

I have a Manipulate to which I am adding and removing Locator points (one of which is different from the others, though that is ...
3
votes
1answer
138 views

Change locator object appearance inside Manipulate

I have read earlier discussions of changing Locator appearance in Manipulate. I would like to change the rendered size of the locator object based on one of the manipulate variables. I can't get ...
4
votes
4answers
330 views

Using Locators in a non-standard Manipulate code

I'm trying to adapt Nasser's method for using a control variable inside Manipulate to selectively choose what part of the code should be recalculated depending on the controls changed (see this ...
2
votes
2answers
76 views

Avoiding RandomVariate update with use of Locator

I am preparing an activity that simulates the response from a noisy spectrometer. The function I use to generate the data has the form: ...
1
vote
1answer
209 views

Using Manipulate with a control variable for selective recalculation

I'm trying to adapt Nasser's method for using a control variable inside Manipulate to selectively choose what part of the code should be recalculated depending on the controls changed. I've also read ...
1
vote
1answer
75 views

Hide output from when mouseover Locator graphic

When the mouse pointer passes over the Locator graphic (or one clicks at any point in the frame), the underlying equation that generates the ContourPlot is visible ...
2
votes
1answer
105 views

Manipulating horizontal and vertical 'guidelines'

Is it possible to create an interactive plot that has drag-down / across horizontal & vertical guides a la Illustrator / InDesign? I would like to generate something like this: I would ideally ...
4
votes
3answers
371 views

Draw plot with locator & slider

I would like to create a plot whereby both the slider and the locator 'draw' the plot. In the following code, the locator & the slider act independently: ...
1
vote
1answer
171 views

Control multiple locators along a plot

Update 1 @ Michael E2, my effort - for what it is worth!: ...
1
vote
1answer
134 views

Two-way locator & slider controls

I was wondering whether it was possible to have a two way control system, whereby one could click and drag both the locator (which would in turn move the sliders), AND click & drag the sliders ...
2
votes
2answers
631 views

Locator to show coordinates of plot

Old I would like to make the locator follow a plot, giving the coordinates as it moves. I don't really know where to start with this one, but I would like the dynamic plot to look something like ...
5
votes
2answers
181 views

Using absolute locator coordinates in Manipulate

In this simplified code below, I'd like to display two plots within Manipulate, and use the Locator controltype to set the value ...
2
votes
2answers
74 views

Constrain movement of Locator (increased t-value)

Continuing with the code at the end this topic, I am now searching for a way of constraining the movement of the locator so that it doesn't "jump" from one "part" of the graph of f to another. So, if ...
2
votes
1answer
94 views

Constrain movement of Locator

Continuing the discussion started in the thread here, I've tried to recreate the code from scratch. I thus looked to constrain the movement of a locator to the graph defined by ...
3
votes
2answers
135 views

Moving a locator based on the movement of another

My problem is: I want two Locators to simulate a vector in the following sense: The first Locator is the base and the second ...
3
votes
2answers
347 views

How do I use Mathematica as a vector drawing program?

Recently I changed my furniture in my room and I am trying to find the best position of each part. I am sure that Mathematica could help! I read the LocatorPane, selecting multiple Locators for ...
1
vote
2answers
215 views

Locator following other locator in DynamicModule

I'm trying to create a dynamic environment where I specify, using two locators, the initial condition (position (x,y) and velocity angle (alpha)) of a 2D particle. To simplify, I'm assuming the ...
2
votes
1answer
172 views

Change the behaviour of a LocatorPane

Normally, LocatorPane detects any single click as in the following example: ...
4
votes
1answer
150 views

Overlaying location pointer on to a png file

So I have started off with importing a png image of size $512\times 1024$ px. I have then created two locators as demonstrated on the Wolfram tutorials: ...
1
vote
1answer
161 views

Behaviour of Locator

I seek advice regarding the constrained behaviour of the Locator: appears confined to square {0,0}->{1,1}. When I change starting position it snaps to this constrained region. The code I am referring ...
3
votes
1answer
551 views

How do I draw a credible velocity vs. time graph using Locators?

This is partly a math question, partly a Mathematica question. For educational purposes, I'm making a simple demonstration to create a velocity over time graph from six locators. On the basis of ...
2
votes
2answers
166 views

Manipulating several values from the same interval

Some of my calculations depend on the choice of several values from the interval [-2, 2] (it is more or less interpolation of a fixed function using the points as parameters). I want to create a ...
0
votes
1answer
84 views

Item Resizing when using Locators

I am having some difficulty in resizing a Stream Plot when using locators: Whenever I try to resize the Stream Plot, one of the locators instead moves to the cursor. ...
4
votes
1answer
159 views

Using the mouse coordinates to index a matrix

I would like to "write" on to a matrix using the mouse. That is, I would like to use the integer value of Locator coordinates (p) to index a matrix. Then, if the mouse button is down, write a 1 in ...
6
votes
2answers
355 views

How to dynamically update Locator[] constraints?

I need to visualize Menelaus' theorem for a triangle with moving locators for each of six points. So the vertexes of the triangle can move in any possible way, and the three points on the sides of the ...
8
votes
1answer
204 views

Locator Appearance

I am using LocatorPane with LocatorAutoCreate -> True. I would like to have the appearance of each new locator be different. ...
4
votes
3answers
686 views

How to align dynamic graphics and an image within an Overlay?

I have dynamic graphics over an image but they won't line up, what am I doing wrong? ...