# useful module
import os, tempfile, random, cStringIO
# setup a temporary working forlder
os.environ['MPLCONfigureDIR'] = tempfile.mkdtemp()
# main matplotlib modules
from matplotlib.backends.backend_agg import FigureCanvasAgg as FigureCanvas
from matplotlib.figure import Figure
# optional for scatter plots
from matplotlib.patches import Ellipse
def plot(title='title',xlab='x',ylab='y',
data={'xxx':[(0,0),(1,1),(1,2),(3,3)],
'yyy':[(0,0,.2),(2,1,0.2),(2,2,0.2),(3,3,0.2)]}):
figure=Figure(frameon=False)
axes=figure.add_subplot(111)
if title: axes.set_title(title)
if xlab: axes.set_xlabel(xlab)
if ylab: axes.set_ylabel(ylab)
keys=sorted(data) # sort data series by name
for key in keys: # for each data series
stream = data[key]
(x,y)=([],[]) # make empty list x and empty
list y
yerr = [] # ... and empty list yerr
(optional)
for point in stream: # for each point in series
x.append(point[0]) # append X coordinate to x
y.append(point[1]) # append Y coordinate to y
if len(point)==3: # if dY, append dY to yerr
yerr.append(point[2])
ell=axes.plot(x, y, linewidth="2") # plot y vs x
if len(yerr)==len(x): # if error bars, display them
axes.errorbar(x, y, yerr=yerr, fmt='o', linewidth="1")
canvas=FigureCanvas(figure)
stream=cStringIO.StringIO()
canvas.print_png(stream)
return stream.getvalue()
def plot_interference():
return plot(data={'interferemce':[(x,x**2) for x in range(100)]})
On Sunday, 13 May 2012 13:02:37 UTC-5, epifanio wrote:
>
>
> i'm looking for a solution, to start to write a web-app to generate graph
> using matplotlib
> the graph needs to be generated using some inputs parameters coming from
> the page itself.
>
> right now i'm rewriting the app from scratch .. but i'm stuck on how to
> integrate a query button to the python code ..
>
> essentially what i need to start is :
>
> a page with a line-edit input box + Jquery widget (a simple button, will
> be enough to learn more)
>
> then connect the button to execute a generic python code that will use as
> input the text in the line-edit
> .. the generic python code will process the text received as input and
> return the results on the same page where the line-edit and the button are.
>
> i hope my description gives you an idea of what i was looking for
>
> Many thanks for any help!
>
>
> Massimo.
>
>
> Il giorno May 11, 2012, alle ore 10:49 AM, Massimo Di Stefano ha scritto:
>
>
> Hi All,
>
> i'm tring to learn web2py, thanks for the wonderful book and for the
> really nice tutorial!
> i'm a bit 'stuck' on how to perform a simple task (i guess it is simple)
> because of my ignorance.
>
> .. i'm bring to update dynamic a graph-chart (generated with matplotlib)
> using a form to pass the input the draw-function.
>
>
> what i have is a controller :
>
> # template_example.py that 'espone' a function 'variables' , it will
> display an image generated by matplotlib using the 'stem_plot' function (in
> the same .py file)
>
>
> # import a lib that generate the data from the url gived as input
>
> from ecoopclimate import Climate
>
> #import some matplotlib methodsm numpy ...
> from pylab import stem, setp, grid, savefig, show, gca, subplot,
> subplots_adjust
> import matplotlib as mpl
> import matplotlib.pyplot as plt
> import datetime as dt
> import numpy as np
>
> # plot function
>
> def stem_plot(data, name):
> data[np.isnan(data)]=0
> fig = plt.figure()
> ax = fig.add_subplot(211)
> mindate = int(data[0][0])
> maxdate = int(data[0][-1])
> date2_1 = dt.datetime(mindate, 1, 1)
> date2_2 = dt.datetime(maxdate, 1, 1)
> delta2 = dt.timedelta(days=365)
> dates2 = mpl.dates.drange(date2_1, date2_2, delta2)
>
> dateFmt = mpl.dates.DateFormatter('%Y')
> ax.xaxis.set_major_formatter(dateFmt)
> fig.autofmt_xdate(bottom=0.1)
> x_p = dates2[np.where(data[1]>=0)[0]]
> y_p = data[1][np.where(data[1]>=0)[0]]
> x_n = dates2[np.where(data[1]<0)[0]]
> y_n = data[1][np.where(data[1]<0)[0]]
>
> markerline, stemlines, baseline = stem(x_p, y_p, 'r-')
> setp(markerline, 'markerfacecolor', 'b')
> setp(baseline, 'color', 'r', 'linewidth', 2)
> setp(stemlines, 'linewidth', 1)
> markerline, stemlines, baseline = stem(x_n, y_n, 'b-')
> setp(markerline, 'markerfacecolor', 'b')
> setp(baseline, 'color', 'r', 'linewidth', 2)
> setp(stemlines, 'linewidth', 1)
> grid()
> setp(gca(), 'xlabel', 'Year', 'ylabel', name)
> fig = '/Users/epifanio/web2py/applications/welcome/static/'+name+'.png'
> dateFmt = mpl.dates.DateFormatter('%Y')
> savefig(fig)
> return fig
> #show()
>
>
> # function connected to the view : variables.html
>
> def variables():
> nao_url =
> 'https://climatedataguide.ucar.edu/sites/default/files/cas_data_files/asphilli/nao_station_djfm.txt'
> clm = Climate()
> NAO = clm.nao(nao_url, 'nao.txt')
> image = stem_plot(NAO['nao'], 'nao')
> return dict(d=URL
> <http://127.0.0.1:8000/examples/global/vars/URL>('static', 'nao.png'))
>
>
> the view template_example/variables.html is :
>
> {{extend 'layout.html'}}
> <h1>Image generated with matplotlib</h1>
>
> <img src="{{=d}}" alt="Red dot" />
>
>
>
> As you can see from the code in stem_plot it takes as input : 'data' and
> 'name'
> i'm hardcoding the var inside the function 'variables'
>
> i need to modify that code adding a 'form' in the view that will take 2
> string as input
>
> nao_url =
> 'https://climatedataguide.ucar.edu/sites/default/files/cas_data_files/asphilli/nao_station_djfm.txt'
>
> image_name = 'imagename'
>
>
> and pass this input to the main function that generate the graph.
>
> Have you any hints on how to do that ?
>
> i'd like to have the form in the same page where the image is displayed
>
> so that i can update the image every time i'll resubmit the form.
>
> i'm a beginner, an example that does something like that will be really
> helpful :)
>
> Many many Thanks for your help!
>
> Massimo.
>
>
>
>
>
>
>
>
>
