The Pan Tompkins algorithm1 for removing noise from an ECG/EKG is cited often. They use a low pass filter, followed by a high pass filter. The output of the high pass filter looks great. But (depending on starting conditions) the output of the low pass filter will continuously increase or decrease. Given enough time, your numbers will eventually get to a size that the programming language cannot handle and rollover. If I run this on an Arduino (which uses a variant of C), it rolls over on the order of 10 seconds. Not ideal. Is there a way to get rid of this bias? I've tried messing with initial conditions, but I'm fresh out of ideas. The advantage of this algorithm is that it's not very computationally intensive and will run comfortably on a modest microprocessor.
1 Pan, Jiapu; Tompkins, Willis J. (March 1985). "A Real-Time QRS Detection Algorithm". IEEE Transactions on Biomedical Engineering. BME-32 (3): 230–236.
Python code to illustrate problem. Uses numpy and matplotlib:
import numpy as np
import matplotlib.pyplot as plt
#low-pass filter
def lpf(x):
y = x.copy()
for n in range(len(x)):
if(n < 12):
continue
y[n,1] = 2*y[n-1,1] - y[n-2,1] + x[n,1] - 2*x[n-6,1] + x[n-12,1]
return y
#high-pass filter
def hpf(x):
y = x.copy()
for n in range(len(x)):
if(n < 32):
continue
y[n,1] = y[n-1,1] - x[n,1]/32 + x[n-16,1] - x[n-17,1] + x[n-32,1]/32
return y
ecg = np.loadtxt('ecg_data.csv', delimiter=',',skiprows=1)
plt.plot(ecg[:,0], ecg[:,1])
plt.title('Raw Data')
plt.grid(True)
plt.savefig('raw.png')
plt.show()
#Application of lpf
f1 = lpf(ecg)
plt.plot(f1[:,0], f1[:,1])
plt.title('After Pan-Tompkins LPF')
plt.xlabel('time')
plt.ylabel('mV')
plt.grid(True)
plt.savefig('lpf.png')
plt.show()
#Application of hpf
f2 = hpf(f1[16:,:])
print(f2[-300:-200,1])
plt.plot(f2[:-100,0], f2[:-100,1])
plt.title('After Pan-Tompkins LPF+HPF')
plt.xlabel('time')
plt.ylabel('mV')
plt.grid(True)
plt.savefig('hpf.png')
plt.show()
raw data in CSV format:
timestamp,ecg_measurement
96813044,2.2336266040
96816964,2.1798632144
96820892,2.1505377292
96824812,2.1603128910
96828732,2.1554253101
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99049100,1.1192570924
99053016,1.1290322542
99056940,1.0997067642
99060840,1.1094819307
99064744,1.1485825777
99068668,1.1925709247
99072588,1.2023460865
99076508,1.1925709247
99080428,1.2023460865
99084340,1.2658846378
99088252,1.3343108892
99092168,1.3587487936
99096084,1.3343108892
99100004,1.3294233083
99103924,1.3636363744
99107860,1.4027370452
99111772,1.3831867027
99115700,1.3343108892
99119628,1.3147605657
99123556,1.3343108892
99127480,1.3587487936
99131404,1.3538612127
99135324,1.3049852848
99139236,1.2756597995
99143156,1.2903225421
99147076,1.3196481466
99151012,1.3147605657
99154924,1.2707722187
99158844,1.2072336673
99162764,1.2023460865
99166676,1.2267839908
99170588,1.2365591526
99174508,1.1974585056
99178420,1.1632453203
99182340,1.1534701585
99186248,1.1876833438
99190164,1.1974585056
99194072,1.1583577394
99197996,1.1192570924
99201916,1.1192570924
99205832,1.1730204820
99209748,1.2072336673
99213668,1.2023460865
99217588,1.1779080629
99221488,1.1876833438
99225412,1.2267839908
99229332,1.2707722187
99233244,1.2609970569
99237152,1.2365591526
99241068,1.2463343143
99244988,1.2805473804
99248900,1.2952101230
99252820,1.2805473804
99256732,1.2316715717
99260660,1.2316715717
99264588,1.2854349613
99268512,1.3391984701
99272436,1.3538612127
99276364,1.3343108892
99280292,1.3391984701
99284212,1.3782991170
99288116,1.4271749496
99292040,1.4369501113
99295964,1.4076246261
99299892,1.4076246261
99303816,1.4662756919
99307740,1.5395894050
99311652,1.5640274047
99315564,1.5444769859
99319484,1.5444769859
99323412,1.5786901473
99327332,1.6275659561
99331252,1.6520038604
99335156,1.6422286987
99339076,1.6275659561
99343004,1.6422286987
99346924,1.6666666030
99350844,1.6568914413
99354764,1.6031280517
99358676,1.5542521476
99362604,1.5542521476
99366532,1.5835777282
99370460,1.5982404708
99374372,1.5835777282
99378300,1.5640274047
99382204,1.5835777282
99386132,1.6373411178
99390056,1.6715541839
99393980,1.6520038604
99397892,1.6275659561
99401812,1.6422286987
99405736,1.6862169265
99409664,1.7106549739
99413580,1.6911046504
99417500,1.6568914413
99421432,1.6715541839
99425348,1.7204301357
99429256,1.8084066390
99433164,1.9208210945
99437068,2.0918865203
99440980,2.3655912876
99444912,2.7321603298
99448828,3.0596284866
99452752,3.2453567981
99456680,3.1867058277
99460600,2.9374389648
99464516,2.5610947608
99468428,2.1163244247
99472356,1.6813293457
99476284,1.3343108892
99480200,1.1436949968
99484112,1.1339198350
99488036,1.2365591526
99491956,1.3440860509
99495864,1.4320625305
99499780,1.5298142433
99503708,1.6422286987
99507636,1.7350928783
99511556,1.7644183635
99515480,1.7399804592
99519396,1.7350928783
99523320,1.7448680400
99527220,1.7350928783
99531140,1.6862169265
99535064,1.5933528900
99538980,1.5102639198
99542892,1.4711632728
99546820,1.4467253684
99550748,1.3978494453
99554668,1.3049852848
99558588,1.2072336673
99562504,1.1485825777
99566428,1.1192570924
99570348,1.0752688646
99574256,1.0068426132
99578176,0.9384163856
99582084,0.9188660621
99585988,0.9188660621
99589900,0.9188660621
99593812,0.8895405769
99597716,0.8748778343
99601636,0.8651026725
99605552,0.9090909004
99609436,0.9481915473
99613356,0.9530791282
99617268,0.9237536430
99621180,0.9335288047
99625080,1.0019550323
99628980,1.0752688646
99632888,1.0801564407
99636792,1.0703812837
99640704,1.0899316024
99644616,1.1436949968
99648536,1.2170088291
99652444,1.2170088291
99656356,1.2023460865
99660268,1.2072336673
99664180,1.2561094760
99668084,1.3000977039
99671980,1.3147605657
99675900,1.2952101230
99679820,1.3000977039
99683728,1.3587487936
99687652,1.4027370452
99691568,1.4222873687
99695484,1.3978494453
99699404,1.3880742835
99703328,1.4173997879
99707248,1.4565005302
99711156,1.4760508537
99715064,1.4271749496
99718988,1.3929618644
99722908,1.3929618644
99726828,1.4076246261
99730748,1.3831867027
99734668,1.3147605657
99738580,1.2561094760
99742492,1.2414467334
99746420,1.2658846378
99750340,1.2658846378
99754252,1.2365591526
99758168,1.2121212482
99762084,1.2365591526
99766012,1.3000977039
99769916,1.3538612127
99773856,1.3685239553
99777780,1.3929618644
99781704,1.4662756919
99785620,1.5640274047
99789532,1.6568914413
99793460,1.6959922313
99797392,1.7057673931
99801312,1.7399804592
99805228,1.7937438488
99809148,1.8377322196
99813072,1.8377322196
99816996,1.8230694770
99820920,1.8475073814
99824840,1.9061583518
99828756,1.9501466751
99832680,1.9599218368
99836608,1.9501466751
99840536,1.9599218368
99844452,2.0087976455
99848364,2.0527858734
99852268,2.0527858734
99856184,2.0283479690
99860092,2.0185728073
99864012,2.0576734542
99867932,2.0967741012
99871836,2.0869989395
99875740,2.0478982925
99879652,2.0234603881
99883564,2.0527858734
99887484,2.1065492630
99891404,2.1163244247
99895332,2.0772237777
99899236,2.0527858734
99903156,2.0821113586
99907076,2.1065492630
99910996,2.1016616821
99914916,2.0576734542
99918828,2.0283479690
99922740,2.0430107116
99926652,2.0821113586
99930572,2.1016616821
99934492,2.0576734542
99938404,2.0332355499
99942316,2.0674486160
99946220,2.1309874057
99950124,2.1749756336
99954052,2.1652004718
99957972,2.1260998249
99961892,2.1456501483
99965804,2.1945259571
99969732,2.2336266040
99973644,2.2189638614
99977564,2.1945259571
99981492,2.2043011188
99985404,2.2482893466
99989332,2.2922775745
99993252,2.2580645084
99997164,2.2238514423
100001084,2.2189638614
100005044,2.2678396701
100009004,2.2776148319
100012956,2.2385141849
100016924,2.1798632144
100020892,2.1603128910
100024844,2.1798632144
100028804,2.2140762805
100032756,2.1798632144
100036716,2.1358749866
100040676,2.1163244247
100044644,2.1358749866
100048604,2.1603128910
100052556,2.1407625675
100056516,2.0967741012
100060468,2.0918865203
100064420,2.1163244247
100068384,2.1407625675
100072340,2.1065492630
100076292,2.0478982925
100080244,2.0332355499
100084196,2.0478982925
100088156,2.0674486160
100092100,2.0332355499
100096056,1.9696969985
100100004,1.9110459327
100103968,1.9061583518
100107928,1.9208210945
100111884,1.8768328666
100115844,1.8181818962
100119812,1.7888562679
100123776,1.8084066390
100127712,1.8475073814
100131672,1.8523949623
100135636,1.8181818962
100139604,1.8035190582
100143560,1.8377322196
100147524,1.8768328666
100151488,1.8719452857
100155448,1.8523949623
100159404,1.8132943153
100163376,1.8426198005
100167328,1.8963831901
100171276,1.9110459327
100175232,1.9061583518
100179188,1.9501466751
100183132,2.1016616821
100187084,2.3216030597
100191036,2.5904202461
100194996,2.8787879943
100198956,3.1769306659
100202916,3.4555230140
100206876,3.5826001167
100210836,3.4115347862
100214804,3.0205278396
100218748,2.5317692756
100222708,2.1016616821
100226676,1.7937438488
100230640,1.5933528900
100234592,1.4858260154
100238548,1.5053763389
100242500,1.6422286987
100246456,1.8377322196
100250424,1.9990224838
100254380,2.0967741012
100258340,2.1652004718
100262284,2.2434017658
100266236,2.3411533832
100270196,2.4242424964
100274140,2.4731183052
100278112,2.4975562095
100282068,2.5562071800
100286020,2.6441838741
100289992,2.7028348445
100293948,2.7077224254
100297908,2.7126100063
100301868,2.7468230724
100305820,2.8054740905
100309764,2.8250244140
100313724,2.7908113002
100317676,2.7370479106
100321636,2.7223851680
100325600,2.7419354915
100329556,2.7517106533
100333516,2.7126100063
100337468,2.6735093593
100341428,2.6686217784
100345392,2.7028348445
100349348,2.7272727489
100353316,2.6881721019
100357260,2.6441838741
100361212,2.6588466167
100365180,2.6832845211
100369140,2.7077224254
100373100,2.6783969402
100377052,2.6148581504
100381012,2.6001954078
100384960,2.6246333122
100388916,2.6490714550
100392860,2.6197457313
100396828,2.5659823417
100400788,2.5562071800
100404740,2.5806450843
100408692,2.6099705696
100412644,2.5904202461
100416588,2.5366568565
100420548,2.5268816947
100424508,2.5610947608
100428460,2.5953078269
100432412,2.5757575035
100436372,2.5171065330
100440324,2.4926686286
100444276,2.5219941139
100448228,2.5366568565
100452196,2.5073313713
100456148,2.4389052391
100460108,2.3949170112
100464068,2.3753666877
100468028,2.3655912876
100471988,2.3069403171
The trick seems to be the initial conditions. Load the first 13 values of input and output of low pass filter to zero and the bias goes away.
#low-pass filter
def lpf(x):
y = x.copy()
for n in range(13):
y[n,1] = 0
x[n,1] = 0
for n in range(len(x)):
if(n < 12):
continue
y[n,1] = 2*y[n-1,1] - y[n-2,1] + x[n,1] - 2*x[n-6,1] + x[n-12,1]
return y
I want to fit two different spectra to my original spectrum. The two different spectra have x and y values of:
x_1 = 1700.42
1700.9
1701.38
1701.86
1702.34
1702.83
1703.31
1703.79
1704.27
1704.75
1705.24
1705.72
1706.2
1706.68
1707.17
1707.65
1708.13
1708.61
1709.09
1709.58
1710.06
1710.54
1711.02
1711.5
1711.99
1712.47
1712.95
1713.43
1713.91
1714.4
1714.88
1715.36
1715.84
1716.33
1716.81
1717.29
1717.77
1718.25
1718.74
1719.22
1719.7
1720.18
1720.66
1721.15
1721.63
1722.11
1722.59
1723.08
1723.56
1724.04
1724.52
1725
1725.49
1725.97
1726.45
1726.93
1727.41
1727.9
1728.38
1728.86
1729.34
1729.82
1730.31
1730.79
1731.27
1731.75
1732.24
1732.72
1733.2
1733.68
1734.16
1734.65
1735.13
1735.61
1736.09
1736.57
1737.06
1737.54
1738.02
1738.5
1738.98
1739.47
1739.95
1740.43
1740.91
1741.4
1741.88
1742.36
1742.84
1743.32
1743.81
1744.29
1744.77
1745.25
1745.73
1746.22
1746.7
1747.18
1747.66
1748.14
1748.63
1749.11
1749.59
1750.07
1750.56
y_1 = 0.00285
0.00289
0.00290
0.00292
0.00297
0.00304
0.00310
0.00314
0.00319
0.00323
0.00327
0.00333
0.00340
0.00344
0.00347
0.00352
0.00358
0.00364
0.00369
0.00374
0.00382
0.00388
0.00392
0.00397
0.00403
0.00408
0.00414
0.00420
0.00428
0.00436
0.00444
0.00451
0.00456
0.00461
0.00468
0.00474
0.00480
0.00486
0.00493
0.00501
0.00509
0.00517
0.00524
0.00530
0.00535
0.00543
0.00551
0.00558
0.00564
0.00571
0.00578
0.00587
0.00594
0.00599
0.00607
0.00615
0.00623
0.00631
0.00636
0.00645
0.00657
0.00666
0.00673
0.00682
0.00688
0.00695
0.00704
0.00713
0.00722
0.00732
0.00741
0.00750
0.00758
0.00768
0.00777
0.00783
0.00788
0.00792
0.00795
0.00799
0.00803
0.00806
0.00807
0.00804
0.00800
0.00795
0.00787
0.00779
0.00767
0.00753
0.00737
0.00719
0.00699
0.00677
0.00652
0.00626
0.00599
0.00572
0.00546
0.00519
0.00492
0.00465
0.00437
0.00413
0.00391
and x_2 = 1700.42 1700.9 1701.38 1701.86 1702.34 1702.83 1703.31 1703.79 1704.27 1704.75 1705.24 1705.72 1706.2 1706.68 1707.17 1707.65 1708.13 1708.61 1709.09 1709.58 1710.06 1710.54 1711.02 1711.5 1711.99 1712.47 1712.95 1713.43 1713.91 1714.4 1714.88 1715.36 1715.84 1716.33 1716.81 1717.29 1717.77 1718.25 1718.74 1719.22 1719.7 1720.18 1720.66 1721.15 1721.63 1722.11 1722.59 1723.08 1723.56 1724.04 1724.52 1725 1725.49 1725.97 1726.45 1726.93 1727.41 1727.9 1728.38 1728.86 1729.34 1729.82 1730.31 1730.79 1731.27 1731.75 1732.24 1732.72 1733.2 1733.68 1734.16 1734.65 1735.13 1735.61 1736.09 1736.57 1737.06 1737.54 1738.02 1738.5 1738.98 1739.47 1739.95 1740.43 1740.91 1741.4 1741.88 1742.36 1742.84 1743.32 1743.81 1744.29 1744.77 1745.25 1745.73 1746.22 1746.7 1747.18 1747.66 1748.14 1748.63 1749.11 1749.59 1750.07 1750.56
y_2 = 0.00182478
0.00198449
0.0021542
0.00230491
0.00248363
0.00269334
0.00289705
0.00308676
0.00330747
0.00358919
0.0038779
0.00415561
0.00444332
0.00474103
0.00507474
0.00542346
0.00576517
0.00613688
0.00651859
0.0068873
0.00727502
0.00767773
0.00808544
0.00851815
0.00894486
0.00935658
0.00979429
0.010245
0.0106727
0.0110844
0.0115191
0.0119878
0.0124556
0.0128823
0.013274
0.0137237
0.0142374
0.0147181
0.0151798
0.0156495
0.0160963
0.016534
0.0169657
0.0173574
0.0177211
0.0180818
0.0184125
0.0187012
0.0189339
0.0191077
0.0192454
0.0193291
0.0193638
0.0193495
0.0192672
0.0191119
0.0188696
0.0185614
0.0181941
0.0176948
0.0170465
0.0162762
0.0153449
0.0142406
0.0129863
0.0115801
0.0100468
0.00844248
0.00692419
0.0055719
0.00435861
0.00340132
0.00270704
0.00213775
0.00168046
0.00134117
0.00109188
9.16595E-4
7.80307E-4
6.65019E-4
5.62731E-4
4.75443E-4
4.42155E-4
4.49867E-4
4.29579E-4
3.9929E-4
3.83002E-4
3.51714E-4
3.38426E-4
3.40138E-4
3.2985E-4
3.27562E-4
3.24274E-4
3.06986E-4
2.92698E-4
3.0041E-4
3.12121E-4
2.84833E-4
2.47545E-4
2.41257E-4
2.34969E-4
2.27681E-4
2.47393E-4
2.60105E-4
2.25817E-4
My original data:
x_orig = 1700.42
1700.9
1701.38
1701.86
1702.34
1702.83
1703.31
1703.79
1704.27
1704.75
1705.24
1705.72
1706.2
1706.68
1707.17
1707.65
1708.13
1708.61
1709.09
1709.58
1710.06
1710.54
1711.02
1711.5
1711.99
1712.47
1712.95
1713.43
1713.91
1714.4
1714.88
1715.36
1715.84
1716.33
1716.81
1717.29
1717.77
1718.25
1718.74
1719.22
1719.7
1720.18
1720.66
1721.15
1721.63
1722.11
1722.59
1723.08
1723.56
1724.04
1724.52
1725
1725.49
1725.97
1726.45
1726.93
1727.41
1727.9
1728.38
1728.86
1729.34
1729.82
1730.31
1730.79
1731.27
1731.75
1732.24
1732.72
1733.2
1733.68
1734.16
1734.65
1735.13
1735.61
1736.09
1736.57
1737.06
1737.54
1738.02
1738.5
1738.98
1739.47
1739.95
1740.43
1740.91
1741.4
1741.88
1742.36
1742.84
1743.32
1743.81
1744.29
1744.77
1745.25
1745.73
1746.22
1746.7
1747.18
1747.66
1748.14
1748.63
1749.11
1749.59
1750.07
1750.56
y_orig = 0.011507
0.0121121
0.0127542
0.0132673
0.0137554
0.0143684
0.0148995
0.0154036
0.0159997
0.0165907
0.0172408
0.0178499
0.018388
0.019089
0.0197701
0.0203572
0.0210393
0.0216564
0.0222324
0.0228305
0.0233166
0.0238667
0.0244387
0.0248918
0.0254159
0.025865
0.026158
0.0265131
0.0267652
0.0269333
0.0271824
0.0273214
0.0274515
0.0274626
0.0271257
0.0269957
0.0270148
0.0267899
0.026651
0.026427
0.0260381
0.0257212
0.0252253
0.0247254
0.0243314
0.0237925
0.0233076
0.0227997
0.0221607
0.0216288
0.0210079
0.020299
0.019702
0.0189881
0.0182382
0.0175053
0.0165944
0.0157524
0.0149355
0.0139746
0.0131167
0.0122307
0.0112948
0.0105009
0.00964397
0.00886105
0.00821613
0.0074542
0.00685928
0.00640136
0.00589444
0.00568351
0.00555559
0.00529467
0.00514074
0.00495682
0.0047789
0.00469697
0.00453005
0.00441613
0.0042912
0.00408328
0.00409536
0.00412444
0.00400951
0.00397959
0.00389367
0.00375074
0.00372082
0.0036819
0.00365497
0.00363905
0.00353413
0.00348721
0.00346528
0.00336936
0.00334044
0.00331251
0.00322459
0.00316767
0.00308874
0.00304882
0.0030859
0.00301798
0.00287005
How do I fit the two spectra to the original spectrum by extracting the coefficients from a least-squares linear fit? I use scipy.optimize.curve_fit to fit using gaussians, but now I need to just fit data.
When I scatterplot the data, it looks like three separate, somewhat asymmetrical peaks - I would think this requires one peak fit for each set of data. Please see my image and code below.
import numpy, matplotlib
import matplotlib.pyplot as plt
x_1 = numpy.array([1700.42, 1700.9, 1701.38, 1701.86, 1702.34, 1702.83, 1703.31, 1703.79, 1704.27, 1704.75, 1705.24, 1705.72, 1706.2, 1706.68, 1707.17, 1707.65, 1708.13, 1708.61, 1709.09, 1709.58, 1710.06, 1710.54, 1711.02, 1711.5, 1711.99, 1712.47, 1712.95, 1713.43, 1713.91, 1714.4, 1714.88, 1715.36, 1715.84, 1716.33, 1716.81, 1717.29, 1717.77, 1718.25, 1718.74, 1719.22, 1719.7, 1720.18, 1720.66, 1721.15, 1721.63, 1722.11, 1722.59, 1723.08, 1723.56, 1724.04, 1724.52, 1725, 1725.49, 1725.97, 1726.45, 1726.93, 1727.41, 1727.9, 1728.38, 1728.86, 1729.34, 1729.82, 1730.31, 1730.79, 1731.27, 1731.75, 1732.24, 1732.72, 1733.2, 1733.68, 1734.16, 1734.65, 1735.13, 1735.61, 1736.09, 1736.57, 1737.06, 1737.54, 1738.02, 1738.5, 1738.98, 1739.47, 1739.95, 1740.43, 1740.91, 1741.4, 1741.88, 1742.36, 1742.84, 1743.32, 1743.81, 1744.29, 1744.77, 1745.25, 1745.73, 1746.22, 1746.7, 1747.18, 1747.66, 1748.14, 1748.63, 1749.11, 1749.59, 1750.07, 1750.56])
y_1 = numpy.array([0.00285, 0.00289, 0.00290, 0.00292, 0.00297, 0.00304, 0.00310, 0.00314, 0.00319, 0.00323, 0.00327, 0.00333, 0.00340, 0.00344, 0.00347, 0.00352, 0.00358, 0.00364, 0.00369, 0.00374, 0.00382, 0.00388, 0.00392, 0.00397, 0.00403, 0.00408, 0.00414, 0.00420, 0.00428, 0.00436, 0.00444, 0.00451, 0.00456, 0.00461, 0.00468, 0.00474, 0.00480, 0.00486, 0.00493, 0.00501, 0.00509, 0.00517, 0.00524, 0.00530, 0.00535, 0.00543, 0.00551, 0.00558, 0.00564, 0.00571, 0.00578, 0.00587, 0.00594, 0.00599, 0.00607, 0.00615, 0.00623, 0.00631, 0.00636, 0.00645, 0.00657, 0.00666, 0.00673, 0.00682, 0.00688, 0.00695, 0.00704, 0.00713, 0.00722, 0.00732, 0.00741, 0.00750, 0.00758, 0.00768, 0.00777, 0.00783, 0.00788, 0.00792, 0.00795, 0.00799, 0.00803, 0.00806, 0.00807, 0.00804, 0.00800, 0.00795, 0.00787, 0.00779, 0.00767, 0.00753, 0.00737, 0.00719, 0.00699, 0.00677, 0.00652, 0.00626, 0.00599, 0.00572, 0.00546, 0.00519, 0.00492, 0.00465, 0.00437, 0.00413, 0.00391])
x_2 = numpy.array([1700.42, 1700.9, 1701.38, 1701.86, 1702.34, 1702.83, 1703.31, 1703.79, 1704.27, 1704.75, 1705.24, 1705.72, 1706.2, 1706.68, 1707.17, 1707.65, 1708.13, 1708.61, 1709.09, 1709.58, 1710.06, 1710.54, 1711.02, 1711.5, 1711.99, 1712.47, 1712.95, 1713.43, 1713.91, 1714.4, 1714.88, 1715.36, 1715.84, 1716.33, 1716.81, 1717.29, 1717.77, 1718.25, 1718.74, 1719.22, 1719.7, 1720.18, 1720.66, 1721.15, 1721.63, 1722.11, 1722.59, 1723.08, 1723.56, 1724.04, 1724.52, 1725, 1725.49, 1725.97, 1726.45, 1726.93, 1727.41, 1727.9, 1728.38, 1728.86, 1729.34, 1729.82, 1730.31, 1730.79, 1731.27, 1731.75, 1732.24, 1732.72, 1733.2, 1733.68, 1734.16, 1734.65, 1735.13, 1735.61, 1736.09, 1736.57, 1737.06, 1737.54, 1738.02, 1738.5, 1738.98, 1739.47, 1739.95, 1740.43, 1740.91, 1741.4, 1741.88, 1742.36, 1742.84, 1743.32, 1743.81, 1744.29, 1744.77, 1745.25, 1745.73, 1746.22, 1746.7, 1747.18, 1747.66, 1748.14, 1748.63, 1749.11, 1749.59, 1750.07, 1750.56])
y_2 = numpy.array([0.00182478, 0.00198449, 0.0021542, 0.00230491, 0.00248363, 0.00269334, 0.00289705, 0.00308676, 0.00330747, 0.00358919, 0.0038779, 0.00415561, 0.00444332, 0.00474103, 0.00507474, 0.00542346, 0.00576517, 0.00613688, 0.00651859, 0.0068873, 0.00727502, 0.00767773, 0.00808544, 0.00851815, 0.00894486, 0.00935658, 0.00979429, 0.010245, 0.0106727, 0.0110844, 0.0115191, 0.0119878, 0.0124556, 0.0128823, 0.013274, 0.0137237, 0.0142374, 0.0147181, 0.0151798, 0.0156495, 0.0160963, 0.016534, 0.0169657, 0.0173574, 0.0177211, 0.0180818, 0.0184125, 0.0187012, 0.0189339, 0.0191077, 0.0192454, 0.0193291, 0.0193638, 0.0193495, 0.0192672, 0.0191119, 0.0188696, 0.0185614, 0.0181941, 0.0176948, 0.0170465, 0.0162762, 0.0153449, 0.0142406, 0.0129863, 0.0115801, 0.0100468, 0.00844248, 0.00692419, 0.0055719, 0.00435861, 0.00340132, 0.00270704, 0.00213775, 0.00168046, 0.00134117, 0.00109188, 9.16595E-4, 7.80307E-4, 6.65019E-4, 5.62731E-4, 4.75443E-4, 4.42155E-4, 4.49867E-4, 4.29579E-4, 3.9929E-4, 3.83002E-4, 3.51714E-4, 3.38426E-4, 3.40138E-4, 3.2985E-4, 3.27562E-4, 3.24274E-4, 3.06986E-4, 2.92698E-4, 3.0041E-4, 3.12121E-4, 2.84833E-4, 2.47545E-4, 2.41257E-4, 2.34969E-4, 2.27681E-4, 2.47393E-4, 2.60105E-4, 2.25817E-4])
x_orig = numpy.array([1700.42, 1700.9, 1701.38, 1701.86, 1702.34, 1702.83, 1703.31, 1703.79, 1704.27, 1704.75, 1705.24, 1705.72, 1706.2, 1706.68, 1707.17, 1707.65, 1708.13, 1708.61, 1709.09, 1709.58, 1710.06, 1710.54, 1711.02, 1711.5, 1711.99, 1712.47, 1712.95, 1713.43, 1713.91, 1714.4, 1714.88, 1715.36, 1715.84, 1716.33, 1716.81, 1717.29, 1717.77, 1718.25, 1718.74, 1719.22, 1719.7, 1720.18, 1720.66, 1721.15, 1721.63, 1722.11, 1722.59, 1723.08, 1723.56, 1724.04, 1724.52, 1725, 1725.49, 1725.97, 1726.45, 1726.93, 1727.41, 1727.9, 1728.38, 1728.86, 1729.34, 1729.82, 1730.31, 1730.79, 1731.27, 1731.75, 1732.24, 1732.72, 1733.2, 1733.68, 1734.16, 1734.65, 1735.13, 1735.61, 1736.09, 1736.57, 1737.06, 1737.54, 1738.02, 1738.5, 1738.98, 1739.47, 1739.95, 1740.43, 1740.91, 1741.4, 1741.88, 1742.36, 1742.84, 1743.32, 1743.81, 1744.29, 1744.77, 1745.25, 1745.73, 1746.22, 1746.7, 1747.18, 1747.66, 1748.14, 1748.63, 1749.11, 1749.59, 1750.07, 1750.56])
y_orig = numpy.array([0.011507, 0.0121121, 0.0127542, 0.0132673, 0.0137554, 0.0143684, 0.0148995, 0.0154036, 0.0159997, 0.0165907, 0.0172408, 0.0178499, 0.018388, 0.019089, 0.0197701, 0.0203572, 0.0210393, 0.0216564, 0.0222324, 0.0228305, 0.0233166, 0.0238667, 0.0244387, 0.0248918, 0.0254159, 0.025865, 0.026158, 0.0265131, 0.0267652, 0.0269333, 0.0271824, 0.0273214, 0.0274515, 0.0274626, 0.0271257, 0.0269957, 0.0270148, 0.0267899, 0.026651, 0.026427, 0.0260381, 0.0257212, 0.0252253, 0.0247254, 0.0243314, 0.0237925, 0.0233076, 0.0227997, 0.0221607, 0.0216288, 0.0210079, 0.020299, 0.019702, 0.0189881, 0.0182382, 0.0175053, 0.0165944, 0.0157524, 0.0149355, 0.0139746, 0.0131167, 0.0122307, 0.0112948, 0.0105009, 0.00964397, 0.00886105, 0.00821613, 0.0074542, 0.00685928, 0.00640136, 0.00589444, 0.00568351, 0.00555559, 0.00529467, 0.00514074, 0.00495682, 0.0047789, 0.00469697, 0.00453005, 0.00441613, 0.0042912, 0.00408328, 0.00409536, 0.00412444, 0.00400951, 0.00397959, 0.00389367, 0.00375074, 0.00372082, 0.0036819, 0.00365497, 0.00363905, 0.00353413, 0.00348721, 0.00346528, 0.00336936, 0.00334044, 0.00331251, 0.00322459, 0.00316767, 0.00308874, 0.00304882, 0.0030859, 0.00301798, 0.00287005])
plt.plot(x_1, y_1, 'o')
plt.plot(x_2, y_2, 'o')
plt.plot(x_orig, y_orig, 'o')
plt.xlabel('X Data') # X axis data label
plt.ylabel('Y Data') # Y axis data label
plt.show()