initial check-in

Scripts/Miscellaneous/op_gs_exp.py

@@ -0,0 +1,39 @@
+# -*- coding: iso-8859-1 -*-
+
+def experiment(): # 'go setup' routine
+    
+    pars = {}
+    pars['P90'] = 2.5e-6		# 90-degree pulse length (s)
+    pars['RD'] = 1              	# delay between scans (s)
+    pars['SW'] = 100e3			# spectrum window (Hz)
+    pars['SI'] = 1*1024			# number of acquisition points
+    pars['DEAD1'] = 10e-6		# receiver dead time (s)  
+
+    while True:
+        yield gs_experiment(pars)       
+
+
+def gs_experiment(pars):
+    e=Experiment()
+
+    # read in variables:
+    P90 = pars['P90']      
+    RD =  pars['RD']
+    SI =  pars['SI']
+    SW =  pars['SW']
+    DEAD1 =  pars['DEAD1'] 
+
+    if P90 > 20e-6:
+        raise Exception("Pulse too long!!!")
+
+    e.ttl_pulse(2e-6, value=1)		# unblank RF amplifier
+    e.ttl_pulse(P90, value=3)		# apply 90-degree pulse
+    e.wait(DEAD1)			# wait for receiver dead time
+    e.record(SI, SW, sensitivity=2)	# acquire signal
+    e.wait(RD)				# wait for next scan
+
+    # write experiment parameters:  
+    for key in pars.keys():
+        e.set_description(key, pars[key])
+
+    return e

Scripts/Miscellaneous/op_gs_res.py

@@ -0,0 +1,54 @@
+# -*- coding: iso-8859-1 -*-
+
+from numpy import *
+
+def result():
+        
+    # loop over the incoming results: 
+    for timesignal in results:
+        if not isinstance(timesignal,ADC_Result): 
+            continue   
+
+        # get list of parameters:
+        pars = timesignal.get_description_dictionary()
+
+        # make a copy of timesignal:
+        fid = timesignal + 0
+
+        # correct for the baseline offset:
+        fid.baseline()
+        
+        # compute the initial phase:
+        phi0 = arctan2(fid.y[1][0], fid.y[0][0]) * 180 / pi
+
+        # do FFT: 
+        fid.exp_window(line_broadening=10)
+        spectrum = fid.fft(samples=2*pars['SI'])
+        spectrum.baseline()
+        spectrum.phase(-phi0)
+
+        # provide timesignal and spectrum to the display tab:
+        data['Timesignal'] = timesignal
+        data["Spectrum"] = spectrum
+
+        # ------------- optional measurements: --------------
+
+        # measure signal intensity:
+        signal = (timesignal +0).phase(-phi0)
+        signal_intensity = sum(signal.y[0:10])      
+
+        # measure spectrum integral:
+        #spectrum_integral = cumsum(spectrum.y[0])
+        spectrum_magnitude = (spectrum+0).magnitude()
+        spectrum_integral =  cumsum(spectrum_magnitude.y[0]) 
+
+        # find the centre of gravity of the spectrum:        
+        cg = argwhere(spectrum_integral > 0.5*spectrum_integral[-1])[0] 
+
+        print ''
+        print '%s%.3e'%('FID intensity = ', signal_intensity)
+        print '%s%.3e'%('Spectrum integral = ', spectrum_integral[-1])
+        print '%s%g%s'%("Spectrum middle frequency = ", spectrum.x[cg], ' Hz')
+        print ''
+
+pass