Python Plotting and Analysis Files
The files listed on this page are for analyzing data acquired with the
SpinCore Technologies iSpin NMR spectrometer. These files
are written in the python programming language. Inexpensive or
free versions of this software can be downloaded from Enthought, Inc.
at https://www.enthought.com/products/epd/. A zip file containing all the files on this page can be downloaded by clicking HERE.
In the analysis files lested below, it is assumed that the data to be
analyzed have been saved as a SpinCore ".txt" file.
New York University
Department of Physics
4 Washington Place
New York, NY 10003
This file reads in a sequence of spincore ".txt" files generated by the
"hahn_echo_sweep", and extracts the size of the echo from each of those
files and plots the result. The echo size is determined by integrating
the absolute value of the signal over a region of the echo. The program
outputs an array can
that can be pasted into a fitting program for further analysis.
Last update: 11/05/2013
Program to plot and analyze CPMG data, in which just a few points (n) are taken from the top of each
echo. The data are generated in the Spincore LabView interface from the
specification of the number of points per echo, n. At the beginning of the FID, and
in the middle of each echo, n
points are collected at the rate given by the parameter 'SW' in the
LabVeiw interface, (or 'bw' in this program). The n points from each echo are
averaged, and the
average is plotted as a function of the time of the given echo. The
fit to a decaying exponential, from which the value of T2 can be extracted.
Last update: 9/22/2013
This program determines T1
from a set of spincore ".txt" files, generated by
running the spincore batch file called 'T1_IR_sweep.bat'. Each ".txt"
file contains the data from an "inversion recovery" sequence, where a
pi pulse inverts the signal, and after a variable delay "tau", a pi/2
pulse is applied and the resulting free-induction decay (FID) is
recorded. The data in the files differ only in the value of tau.
Fitting the size of the FID as a function of tau to an exponential
decay allows one to extract the spin-lattice relaxation time T1.
More specifically, this program:
Last update: 2/21/2012
- plots the data from each of the ".txt" data files.
- Integrates over the resonance line in the complex frequency
spectrum to get the 'size' of the signal for each value of tau.
- For each value of tau, rotates the integrated signal onto the
- Fits the signal size as a function of tau to a decaying
exponential and prints the fit parameters (including value of T1), and plots both the
data and fit.
This routine reads in a spincore ".txt" file, and plots the data as
well as the
fft of the data in that file.
Last update: 10/7/2012
This program reads in a sequence of spincore ".txt" files generated by
the iSpin NMR spectrometer as a result of running the batch file
The program extracts the "amplitude" of the echo in each file by
integrating the absolute value over the width of the echo. The range of
integration is given by the parameter sequence, extracts the `echo
amplitude' from each file, generates and prints an array from these
numbers and plots the result, and fits a theoretical curve modeling the
effects of diffusion to the data. The effects
of T2, the
"spin-spin" relaxation time is also taken into account.
User needs to set some parameters before running this program. These
parameters are: rootname: taumin: Minimum value of tau Delta_tau:
Increment in tau from one file to the next Ntaus: Number of different
values of tau
They can be obtained from the file `Hahn_echo_sweep.bat'. The
parameters can be
set by editing the values between the two signs that say: "User sets
values of parameters".
Last update: 11/05/2013
This routine reads in and plots a sequence of spincore '.txt' files.
The plots are saved to disk with filename 'xxx.pdf', where 'xxx.txt' is
the file name containing the data. Derived from the program
plot_ispin_forloop, written by Greg Lemberskiy.
Last update: 1/30/2012
This routine reads in a spincore ".txt" file, and plots the time data
in that file as well as the frequency data (FFT). Since the interesting
part of the data is at low frequencies, the frequency range of the plot
reduced by a scale factor 'sf'.
Last update: 10/07/2012
This routine reads in a spincore ".txt" file, and plots the data in
Last update: 11/5/2013