added fitting example from 8.14; doesn't include data files

1 files changed, 132 insertions, 0 deletions

diff --git a/example_exersize.py b/example_exersize.py
new file mode 100644
index 0000000..803ccac
--- /dev/null
+++ b/example_exersize.py
@@ -0,0 +1,132 @@
+
+from pylab import *
+import pylab
+from scipy import *
+
+def plotfit_gaus(indict,newfig=True,txtp=True):
+    if not indict.has_key('x'):
+        print "forgot to use ret_all on the fittodata?";
+        return;
+    p1 = indict['params'];
+    x = indict['x']
+    y = indict['y']
+    err = indict['err']
+    ffunc = indict['ffunc']
+    pylab.errorbar(x,y,fmt='b.',yerr=err)
+    d=pylab.plot(x,y,'k.')
+    fx = x
+    if pylab.size(fx) < 100:
+        fx = r_[min(x):max(x):(max(x)-min(x))/150.]
+    f=pylab.plot(fx,ffunc(p1,fx),'r-')
+    #fy = indict['ffunc'](indict['params'],indict['x'])
+    pylab.title("Gaussian Fit of Events")
+    pylab.xlabel("Number of Charged Particles")
+    pylab.ylabel("Events")
+    p1 = indict['params']
+    p1_err = indict['param_error']
+
+    ax = pylab.gca()
+#    ax.set_xlim([-1,14])
+    extra_txt = 'reduced chi squared: %g'\
+        % (indict['rchisqr'])
+    for i in range(scipy.size(p1)):
+        extra_txt += '\np[%i]: %g +/- %g' \
+            % (i,p1[i],p1_err[i]);
+
+#    if(pylab.size(p1) == 2):
+#        extra_txt = 'reduced chi squared: %g\np[0]: %g\np[1]: %g' \
+#            % (indict['rchisqr'],p1[0],p1[1])
+#    else:
+#        extra_txt= 'reduced chi squared:%g\np[0]:%g, +/- %g\n p[1]:%g\np[2]:%g' \
+#            % (indict['rchisqr'],p1[0],p1[1],p1[2])
+
+    if txtp:
+        t = pylab.text(.77, .75, extra_txt,
+            horizontalalignment='center',
+            verticalalignment='center',
+            transform = ax.transAxes)
+        pylab.legend((d,f),('Data', 'Fit'))
+
+def plotfit_poiss(indict,newfig=True,txtp=True):
+    if not indict.has_key('x'):
+        print "forgot to use ret_all on the fittodata?";
+        return;
+    p1 = indict['params'];
+    x = indict['x']
+    y = indict['y']
+    err = indict['err']
+    ffunc = indict['ffunc']
+#    if newfig: pylab.figure();
+    pylab.errorbar(x,y,fmt='b.',yerr=err)
+    d=pylab.plot(x,y,'k.')
+    fx = x
+    if pylab.size(fx) < 100:
+        fx = r_[min(x):max(x):(max(x)-min(x))/150.]
+    p1= p1[0]
+    if txtp:
+        f2=pylab.plot(fx,ffunc(p1,fx),'r-')
+    else:
+        f2=pylab.plot(fx,ffunc(p1,fx),'g-')
+    #fy = indict['ffunc'](indict['params'],indict['x'])
+    pylab.title("Poisson Fit of Events")
+    pylab.xlabel("Number of Charged Particles")
+    pylab.ylabel("Events")
+    p1 = indict['params']
+    p1_err = indict['param_error']
+
+    p1= p1[0]
+    ax = pylab.gca()
+    #ax.set_xlim([-1,20])
+    extra_txt = 'reduced chi squared: %g'\
+        % (indict['rchisqr'])
+    for i in range(scipy.size(p1)):
+        if type(p1_err) is not type(9.2):
+            extra_txt += '\np[%i]: %g +/- %g' \
+                % (i,p1[i],p1_err[i]);
+        else:
+            extra_txt += '\np[%i]: %g' \
+                % (i,p1[i]);
+
+#    if(pylab.size(p1) == 2):
+#        extra_txt = 'reduced chi squared: %g\np[0]: %g\np[1]: %g' \
+#            % (indict['rchisqr'],p1[0],p1[1])
+#    else:
+#        extra_txt= 'reduced chi squared:%g\np[0]:%g, +/- %g\n p[1]:%g\np[2]:%g' \
+#            % (indict['rchisqr'],p1[0],p1[1],p1[2])
+    if txtp:
+        t = pylab.text(.77, .75, extra_txt,
+            horizontalalignment='center',
+            verticalalignment='center',
+            transform = ax.transAxes)
+    if txtp:
+        pylab.legend((d,f2),('Data', 'Fit'))
+
+lsd = pylab.load("lineshapedata.txt")
+ls1 = pylab.load("lineshape1.txt")
+
+rawlsd = []
+for i in range(size(lsd[0,:])):
+    for j in range(lsd[1,i]):
+                rawlsd.append(lsd[0,i])
+
+rawls1 = []
+for i in range(size(ls1[0,:])):
+    for j in range(ls1[1,i]):
+                rawls1.append(ls1[0,i])
+
+plotfit(fittodata_lorentz(lsd[0,:],lsd[1,:],[50.0,20.0],err=sqrt(lsd[1,:]),ret_all=True))
+hist(rawlsd, bins=lsd[0,:],align='center',facecolor="lightblue")
+pylab.title("Lorentzian fit to lineshapedata.txt")
+plotfit(fittodata_gaussian(lsd[0,:],lsd[1,:],[50.0,20.0],err=sqrt(lsd[1,:]),ret_all=True))
+hist(rawlsd, bins=lsd[0,:],align='center',facecolor="lightblue")
+pylab.title("Gaussian fit to lineshapedata.txt")
+
+plotfit(fittodata_lorentz(ls1[0,:],ls1[1,:],[50.0,20.0],err=sqrt(ls1[1,:]),ret_all=True))
+hist(rawls1, bins=ls1[0,:],align='center',facecolor="lightblue")
+pylab.title("Lorentzian fit to lineshape1.txt")
+plotfit(fittodata_gaussian(ls1[0,:],ls1[1,:],[50.0,20.0],err=sqrt(ls1[1,:]),ret_all=True))
+hist(rawls1, bins=ls1[0,:],align='center',facecolor="lightblue")
+pylab.title("Gaussian fit to lineshape1.txt")
+
+#pylab.figure()
+#plot(ls1[0,:],ls1[1,:])