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These are questions asked by Teep

Good day.

I am working on a network flow problem that uses a linear programming (simplex) technique.The flow is directed across 3 regions (a, b, and c) and there are 2 nodes within region a, 4 nodes in region b, and 5 nodes in region c.

I wish to determine the minimum cost from regions a to c and from regions b to c that satisfies the requirement of each of the 5 nodes in region c. The objective and constraints are constructed and Maple produces the minimum solution (see attached). While the output is useful when the number of nodes is small, I would like to extend this to a larger-scale case and so the output would need to be more user-friendly / graphic.

I have 2 questions - 

1. Does anyone know a way to attach labels for each region and each node to these solution matrices?
    For instance -  the first matrix, x, specifies a quantity of 2,000 that flows from node #1 in region a to node #2 in region b
2. Is it possible to produce a network graph showing the directed flow from each region and from node to node?

Thanks to all for reading this!


Good day all.

My particular question concerns a Traveling Salesman-type problem.

Suppose I wish to move along the x-y plane and visit specific nodes (see the attached worksheet).

Starting at the origin, A, I intend to visit four locations, B to E, and finally return to the origin point. These nodes may be visited in any order - but, my total distance travelled must be a minimum.
However, my direction of travel is restricted; namely:

1. Movement is limited to the x and y-directions only (up and down as well as left and right)
2. Horizontal (left or right) movement is permitten only at y=1 and y=10

This second rule restricts me from turning left or right in between y= 1 and 10.
The Traveling Salesman routine (attached) is constructed to select a tour that is confined to orthogonal movement but it does not observe the second restriction (i.e. move left or right when you reach y=1 or y=10).

Is there any way in which I can build this condition into the routine so that the movement along the circuit observes the restrictions? 

If so - is it possible to graphically illustrate the order of travel (using arrows from point-to-point) on a point plot?

I appreciate you taking the time to read this.


Good day.

When I export an animated 3D (surface contour) plot to a gif format, the image is incomplete (please see attached file).

Can anyone suggest a way to reformulate the expressions so the animated plot can be exported to Powerpoint intact?

Thanks for reading!


Good day!

I would welcome any help to explain how to plot a simple function, z, of two variables, (x, y) so that I can show the relationships between variables.

Basically, I need to plot a family of z-curves for varying x and y values and also would like to understand how to display the z-y and z-x plots. 

Thanks for reading!


Good day all.

If I generate a list containing (say) 100 elements or more, and each element is an ordered pair - is it possible to assign a letter to each element? The first 26 elements will have equal A to Z, the next 26 will take A1 to Z1, and so on.

For example if the list is [ [5,3], [2,5], ..., [3,1]], how do I construct it to become [A=[5,3], B=[2,5], ..., V3=[3,1]]?

Please see attached.

Thank's a lot for your time.


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