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    <p>If you want to define the point pseudo randomly you can use <a href="http://docs.python.org/2/library/random.html" rel="nofollow noreferrer">random.randrange</a>.</p> <pre><code>from random import randrange as rd from math import sqrt ptBlu=[11,12,13] #example of blu point ptRedx=ptBlu[0]+rd(-10,10,1) #x coordinate of a red point(rd is the function stand for random.randrange) ptRedy=ptBlu[1]+rd(-10,10,1) #y coordinate of a red point ptRedz=ptBlu[2]+rd(-10,10,1) #z coordinate of a red point ptRed=[ptRedx,ptRedy,ptRedz] #list with the x,y,z coordinates </code></pre> <p>If you want to create a series of points with a distance greater than a certain one from a certain point avoiding to create points with the same coordinates. You have to do something more elaborate. This is the example for a 2D plane as your draw. For a 3D example simply add the third coordinate and adjust the formulae.</p> <pre><code>redptlist=[] #inizialize a void lists for red point coordinates xredptlist=[] yredptlist=[] pointcounter=0 #initizlize counter for the while loop mindist=2.5#set the minimum euclidean distance beyond you want to create the points maxdist=12#set the maximum euclidean distance redpoint can have from blu point maxc=int(sqrt((maxdist**2)/2)) #from the euclidean distance formula you can get the max coordinate while True: #create a potentailly infinite loop! pay attention! if pointcounter&lt;20: #set the number of point you want to add (in this case 20) x_RedPtshift=rd(-maxc,maxc,1) #x shift of a red point y_RedPtshift=rd(-maxc,maxc,1) #y shift of a red point if sqrt(x_RedPtshift**2+y_RedPtshift**2)&gt;mindist: #if the point create go beyond the minimum distance ptRedx=ptBlu[0]+ x_RedPtshift#x coordinate of a red point ptRedy=ptBlu[1]+ y_RedPtshift #y coordinate of a red point ptRed=[ptRedx,ptRedy] #list with the x,y,z coordinates if ptRed not in redptlist: #avoid to create red point with the same coordinates redptlist.append(ptRed) # add to a list with this notation [x1,y1],[x2,y2] xredptlist.append(ptRedx) # add to a list with this notation [x1,x2,x3...] for plotting yredptlist.append(ptRedy) # add to a list with this notation [y1,y2,y3...] for plotting pointcounter+=1 #add one to the counter of how many points you have in your list else: #when pointcounter reach the number of points you want the while cicle ends break </code></pre> <p>Try to test it with <a href="/questions/tagged/matplotlib" class="post-tag" title="show questions tagged &#39;matplotlib&#39;" rel="tag">matplotlib</a>:</p> <pre><code>import matplotlib.pyplot as plt plt.plot(ptBlu[0],ptBlu[1],'bo')#plot blu point plt.plot(xredptlist, yredptlist, 'ro')#plot red points minCircle=plt.Circle((ptBlu[0],ptBlu[1],1),mindist,color='b',fill=False)#draw circle with min distance maxCircle=plt.Circle((ptBlu[0],ptBlu[1],1),maxdist,color='r',fill=False) fig = plt.gcf() fig.gca().add_artist(minCircle) fig.gca().add_artist(maxCircle) plt.axis([-3, 25, -1, 25]) plt.axes().set_aspect('equal', 'box') plt.grid(True) plt.show() </code></pre> <p>Here is the result: <img src="https://i.stack.imgur.com/c7Hzn.png" alt="plotting result"></p>
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    1. POHow to get a series of random points in a specific range of distances from a reference point and generate xyz coordinates
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    1. COthank GM. its working. But if i want to generate point from a point away from 2.5 cm in all direction. how to do that.
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    2. COI've improved the answer. I suggest you to change the title in something like: _How to get a series of random points in a specific range of distances from a reference point_ or something like that maybe you'll have more answers.
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    3. COThanks GM. That exactly i wanted. What you have done in your answers. The second ans is not working. I am trying to figure out.
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