[Matplotlib-users] query on weighted matrix example
Friends,
In the mpl site, i found the an example code called hinton_demo to plot
weighted matrix in the following link.
http://matplotlib.sourceforge.net/examples/api/hinton_demo.html?highlight=hinton
I used the same script (attached test.py) making a slight modification in
the following section of the code pasted below. I just included more color
range and modified the size as np.sqrt(np.abs(w))/5.
However when i run the script with test data (attached test.dat), i found
that the size of the square and color are not matching. For instance the
size of the squares at position 4,3 and 7,6 are small but the color (black)
is not relevant to the size. I am not getting what is going wrong. Kindly
help to resolve the problem.
The script and test data are attached.
*Section of the code modified*
for (x,y),w in np.ndenumerate(W):
if w > 0: color = 'white'
else: color = 'black'
size = np.sqrt(np.abs(w))
rect = Rectangle([x - size / 2, y - size / 2], size, size,
facecolor=color, edgecolor=color)
ax.add_patch(rect)
#!/usr/bin/env python
#Initial idea from David Warde-Farley on the SciPy Cookbook
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.patches import Rectangle
from matplotlib.ticker import NullLocator
import matplotlib as mpl
from sys import argv
# This script was extraced from mpl website.
mpl.rcParams['font.size']=7
mpl.rcParams['font.family']='bold'
mat=np.loadtxt(argv[1])
def hinton(W, maxWeight=None, ax=None):
"""
Draws a Hinton diagram for visualizing a weight matrix.
"""
if not ax:
fig = plt.figure(figsize=(3.60,3.60),dpi=300)
ax = fig.add_subplot(1, 1, 1)
if not maxWeight:
maxWeight = 2**np.ceil(np.log(np.abs(W).max())/np.log(2))
ax.patch.set_facecolor('white')
ax.set_aspect('equal', 'box')
ax.xaxis.set_major_locator(NullLocator())
ax.yaxis.set_major_locator(NullLocator())
for (x,y),w in np.ndenumerate(W):
if w < 2.0: color = 'red'
elif 2.1 < w < 4.0: color='blue'
elif 4.1 < w < 6.0: color='green'
else: color = 'black'
size = np.sqrt(np.abs(w))/5
rect = Rectangle([x - size / 2, y - size / 2], size, size,facecolor=color, edgecolor=color)
ax.add_patch(rect)
ax.autoscale_view()
# Reverse the yaxis limits
ax.set_ylim(*ax.get_ylim()[::-1])
hinton(mat)
plt.xticks(np.arange(0,9,1))
plt.yticks(np.arange(0,9,1))
plt.ylim([-0.5,8.5])
plt.xlim([-0.5,8.5])
plt.savefig('test.png',dpi=300,bbox_inches='tight')
#plt.show()
test.dat
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Re: [Matplotlib-users] query on weighted matrix example
Friends, I have solved the problem by myself. I gave if w < 2.0: color = 'red' if 2.1 < w > 4.0: color='blue' So wherever the value there is a value like 2.03 or 2.05, the color was shown as black instead of red/blue. Thanks, Bala On Mon, Sep 26, 2011 at 9:25 AM, Bala subramanian wrote: > Friends, > In the mpl site, i found the an example code called hinton_demo to plot > weighted matrix in the following link. > > > http://matplotlib.sourceforge.net/examples/api/hinton_demo.html?highlight=hinton > > I used the same script (attached test.py) making a slight modification in > the following section of the code pasted below. I just included more color > range and modified the size as np.sqrt(np.abs(w))/5. > > However when i run the script with test data (attached test.dat), i found > that the size of the square and color are not matching. For instance the > size of the squares at position 4,3 and 7,6 are small but the color (black) > is not relevant to the size. I am not getting what is going wrong. Kindly > help to resolve the problem. > > The script and test data are attached. > > *Section of the code modified* > > for (x,y),w in np.ndenumerate(W): > if w > 0: color = 'white' > else: color = 'black' > size = np.sqrt(np.abs(w)) > rect = Rectangle([x - size / 2, y - size / 2], size, size, > facecolor=color, edgecolor=color) > ax.add_patch(rect) > > -- All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity and more. Splunk takes this data and makes sense of it. Business sense. IT sense. Common sense. http://p.sf.net/sfu/splunk-d2dcopy1___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
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Re: [Matplotlib-users] Assign colors to list?
On Mon, Sep 26, 2011 at 12:05 PM, Katie Boyle wrote: > Hi All, > > I was wondering how I take a list of 250 discrete values and match up each > value in the list to a color in the gist_rainbow colormap. I want the > highest value to be red, and the lowest value to be blue. I then want to > plot a point for each value in the list, and the point's color should > represent its value. I cannot use contourf or any other function that does > this automatically on a continuous grid--I need to plot individual points. I think you are looking for "scatter", with the "c" argument being your intensity value. You can pass the gist_rainbow colormap to the scatter function via the cmap argument. See these examples http://matplotlib.sourceforge.net/examples/pylab_examples/scatter_demo.html http://matplotlib.sourceforge.net/examples/pylab_examples/scatter_demo2.html -- All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity and more. Splunk takes this data and makes sense of it. Business sense. IT sense. Common sense. http://p.sf.net/sfu/splunk-d2dcopy1 ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Assign colors to list?
On Mon, Sep 26, 2011 at 12:24 PM, John Hunter wrote: > On Mon, Sep 26, 2011 at 12:05 PM, Katie Boyle wrote: >> Hi All, >> >> I was wondering how I take a list of 250 discrete values and match up each >> value in the list to a color in the gist_rainbow colormap. I want the >> highest value to be red, and the lowest value to be blue. I then want to >> plot a point for each value in the list, and the point's color should >> represent its value. I cannot use contourf or any other function that does >> this automatically on a continuous grid--I need to plot individual points. > > I think you are looking for "scatter", with the "c" argument being > your intensity value. You can pass the gist_rainbow colormap to the > scatter function via the cmap argument. See these examples > > http://matplotlib.sourceforge.net/examples/pylab_examples/scatter_demo.html > http://matplotlib.sourceforge.net/examples/pylab_examples/scatter_demo2.html Eg, In [43]: x, y, c = np.random.randn(3, 100) In [44]: plt.scatter(x, y, c=c, cmap='gist_rainbow') Out[44]: -- All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity and more. Splunk takes this data and makes sense of it. Business sense. IT sense. Common sense. http://p.sf.net/sfu/splunk-d2dcopy1 ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
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