matplotlib

Matplotlib: plotting discrete values

I am trying to plot the following ! from numpy import * from pylab import * import random for x in range(1,500): y = random.randint(1,25000) print(x,y) plot(x,y) show() However, I keep getting a blank graph (?). Just to make sure that the program logic is correct I added the code print(x,y), just the confirm that (x,...

matplotlib.pyplot/pylab not updating figure while isinteractive(), using ipython -pylab

There are a lot of questions about matplotlib, pylab, pyplot, ipython, so I'm sorry if you're sick of seeing this asked. I'll try to be as specific as I can, because I've been looking through people's questions and looking at documentation for pyplot and pylab, and I still am not sure what I'm doing wrong. On with the code: Goal: plot ...

AttributeError while adding colorbar in matplotlib

The following code fails to run on Python 2.5.4: from matplotlib import pylab as pl import numpy as np data = np.random.rand(6,6) fig = pl.figure(1) fig.clf() ax = fig.add_subplot(1,1,1) ax.imshow(data, interpolation='nearest', vmin=0.5, vmax=0.99) pl.colorbar() pl.show() The error message is C:\temp>python z.py Traceback (most re...

matplotlib equivalent for MATLABs truesize()

I am new to matplotlib and python and would like to display an image so that 1 pixel of the image is actually represented by 1 pixel in the figure. In MATLAB, this is achieved with the command truesize(). How can I do this in Python? I tried playing around with the imshow() arguments as well as set_dpi() and set_figwidth()/set_figheight...

Create matplotlib legend out of the figure

I added the legend this way: leg = fig.legend((l0,l1,l2,l3,l4,l5,l6), ('0 Cl : r2, slope, origin', '1 Cl :'+str(r1b)+' , '+str(m1)+' , '+str(b1), '2 Cl :'+str(r2b)+' , '+str(m2)+' , '+str(b2), '3 Cl :'+str(r3b)+' , '+str(m3)+' , '+str(b3), '4 Cl :'+str(r4b)+' , '+str(m4)+' , '+str(b4), '5 Cl :'+str(r5b)+...

Putting newline in matplotlib label with TeX in Python?

How can I add a newline to a plot's label (e.g. xlabel or ylabel) in Matplotlib? For example, plt.bar([1, 2], [4, 5]) plt.xlabel("My x label") plt.ylabel(r"My long label with $\Sigma_{C}$ math \n continues here") Ideally i'd like the y-labeled to be centered too. Is there a way to do this? It's important that the label have both t...

matplotlib - write TeX on Qt form

I'd like to add some TeX text to my Qt form, like label - just text, no graph, no lines, no borders, just TeX. I thought something like this: render TeX to bitmap and then place that bitmap on form, e.g. into QLabel. Or even better - use some backend, add it to form and use something tex_label.print_tex(<tex code>). Seems matplotplot has...

matplotlib analog of R's `pairs`

R has a useful function pairs that provides nice matrix of plots of pairwise connections between variables in a data set. The resulting plot looks similar to the following figure, copied from this blog post: Is there any ready to use function based on python's matplolib? I have searched its gallery, but couldn't find anything that res...

error when plotting log'd array in matplotlib/scipy/numpy

I have two arrays and I take their logs. When I do that and try to plot their scatter plot, I get this error: File "/Library/Python/2.6/site-packages/matplotlib-1.0.svn_r7892-py2.6-macosx-10.6-universal.egg/matplotlib/pyplot.py", line 2192, in scatter ret = ax.scatter(x, y, s, c, marker, cmap, norm, vmin, vmax, alpha, linewidths, ...

Python: x-y-plot with matplotlib

I want to plot some data. The first column contains the x-data. But matplotlib doesnt plot this. Where is my mistake? #fresnel formula import numpy as np from numpy import cos from scipy import * from pylab import plot, show, ylim, yticks from matplotlib import * from pprint import pprint n1 = 1.0 n2 = 1.5 #alpha, beta, intensity dat...

matplotlib: working with range in x-axis

Hey Guys, I'm trying to do a basic line graph here, but I can't seem to figure out how to adjust my x axis. And here is the error I get when I try adjusting my range. from pylab import * plot ( range(0,11),[9,4,5,2,3,5,7,12,2,3],'.-',label='sample1' ) plot ( range(0,11),[12,5,33,2,4,5,3,3,22,10],'o-',label='sample2' ) xlabel('x axi...

draw csv file data as a heatmap using numpy and matplotlib

Hello all, I was able to load my csv file into a numpy array: data = np.genfromtxt('csv_file', dtype=None, delimiter=',') Now I would like to generate a heatmap. I have 19 categories from 11 samples, along these lines: COG station1 station2 station3 station4 COG0001 0.019393497 0.1831224...

How to plot non-numeric data in Matplotlib

I wish to plot the time variation of my y-axis variable using Matplotlib. This is no problem for continuously discrete data, however how should this be tackled for non-continuous data. I.e. if I wanted to visualise the times at which my car was stationary on the way to work the x-axis would be time and the y-axis would be comprised of ...

making binned boxplot in matplotlib with numpy and scipy in Python

I have a 2-d array containing pairs of values and I'd like to make a boxplot of the y-values by different bins of the x-values. I.e. if the array is: my_array = array([[1, 40.5], [4.5, 60], ...]]) then I'd like to bin my_array[:, 0] and then for each of the bins, produce a boxplot of the corresponding my_array[:, 1] values that fall ...

Using PyLab to create a 2D graph from two separate lists

Hey Guys, This seems like a basic problem with an easy answer but I simply cannot figure it out no matter how much I try. I am trying to create a line graph based on two lists. For my x-axis, I want my list to be a set of strings. x_axis_list = ["Jan-06","Jul-06","Jan-07","Jul-07","Jan-08"] y_axis_list = [5,7,6,8,9] Any suggestion...

Delete lines in matplotlib

Hi, I need to delete all the lines on a subplot, to then redraw them (i'm making a redraw function to be used when i add/remove some lines) How do I do it? ...

matplotlib plots one time only

I'm having a problem with matplotlib where it only plots a line the first time i run the draw() function I made for it. My code is like this: I have graphPanel.py: (stripped to the essentials) class GraphPanel(wx.Panel): def __init__(self, parent): wx.Panel.__init__(self, parent) self.figure = Figure() self...

Python: Plot some data (matplotlib) without GIL

Hello all, my problem is the GIL of course. While I'm analysing data it would be nice to present some plots in between (so it's not too boring waiting for results) But the GIL prevents this (and this is bringing me to the point of asking myself if Python was such a good idea in the first place). I can only display the plot, wait till ...

plotting stem with a continuous line

Hi All I need to plot a stem plot of my signal using python and matplotlib. I saw the example and the code but the line connecting the black big dot and the x-axis is not a continous line. Do you know whether is possible and how to get a straight line instead? Thank you very much AFG #!/usr/bin/env python from pylab import * x = l...

Periodically updating data in a matplotlib figure embedded in a QWidget

I have a thread that updates some data periodically. I want do visualize the data with matplotlib. When the thread updates the data, the plot should be updated as well. I tried embedding a matplotlib.FigureCanvas(see following snippet) in a QWidget... class MplSubPlotCanvas(FigureCanvas): def __init__(self, parent=None): se...