This is my own data format
$sin(\theta)/\theta$
-29.9	-0.033394483
-29.7	-0.033316063
-29.5	-0.03189937
-29.3	-0.029182928
-29.1	-0.025257719
-28.9	-0.020264268
-28.7	-0.014387719
-28.5	-0.007851075
-28.3	-0.00090683
-28.1	0.006172675
-27.9	0.013105829
-27.7	0.01961284
-27.5	0.02542691
-27.3	0.030305051
-27.1	0.034038111
-26.9	0.0364596
-26.7	0.037452949
-26.5	0.036956892
-26.3	0.034968732
-26.1	0.031545326
-25.9	0.026801725
-25.7	0.020907478
-25.5	0.01408072
-25.3	0.006580237
-25.1	-0.001304198
-24.9	-0.00926288
-24.7	-0.016978175
-24.5	-0.024137042
-24.3	-0.030443563
-24.1	-0.035630996
-23.9	-0.039472865
-23.7	-0.041792638
-23.5	-0.042471576
-23.3	-0.041454427
-23.1	-0.0387527
-22.9	-0.03444534
-22.7	-0.028676754
-22.5	-0.021652201
-22.3	-0.0136307
-22.1	-0.004915683
-21.9	0.004156275
-21.7	0.013228233
-21.5	0.021936698
-21.3	0.029925943
-21.1	0.036862283
-20.9	0.042447729
-20.7	0.046432499
-20.5	0.048625844
-20.3	0.048904749
-20.1	0.047220127
-19.9	0.043600206
-19.7	0.038150935
-19.5	0.031053327
-19.3	0.022557791
-19.1	0.012975613
-18.9	0.002667867
-18.7	-0.007967862
-18.5	-0.018512466
-18.3	-0.028541453
-18.1	-0.037641645
-17.9	-0.045427772
-17.7	-0.05155833
-17.5	-0.055750057
-17.3	-0.05779043
-17.1	-0.057547661
-16.9	-0.054977752
-16.7	-0.05012825
-16.5	-0.043138506
-16.3	-0.034236336
-16.1	-0.023731144
-15.9	-0.012003684
-15.7	0.000507209
-15.5	0.013320483
-15.3	0.025930756
-15.1	0.037827607
-14.9	0.048515527
-14.7	0.057533798
-14.5	0.064475521
-14.3	0.069005032
-14.1	0.070873006
-13.9	0.069928597
-13.7	0.066128083
-13.5	0.059539587
-13.3	0.050343591
-13.1	0.038829119
-12.9	0.025385615
-12.7	0.010490712
-12.5	-0.005305752
-12.3	-0.021400959
-12.1	-0.037160947
-11.9	-0.051944295
-11.7	-0.065126802
-11.5	-0.076126276
-11.3	-0.084426482
-11.1	-0.089599332
-10.9	-0.091324427
-10.7	-0.089405142
-10.5	-0.083780549
-10.3	-0.074532603
-10.1	-0.061888183
-9.9	-0.046215747
-9.7	-0.028016559
-9.5	-0.007910644
-9.3	0.013382196
-9.1	0.035065754
-8.9	0.056294478
-8.7	0.07620336
-8.5	0.09393966
-8.3	0.108695402
-8.1	0.119739483
-7.9	0.126448271
-7.7	0.128333537
-7.5	0.125066664
-7.3	0.116498167
-7.1	0.102671696
-6.9	0.08383185
-6.7	0.060425361
-6.5	0.033095383
-6.3	0.002668873
-6.1	-0.029862706
-5.9	-0.063368926
-5.7	-0.096611499
-5.5	-0.128280059
-5.3	-0.157031593
-5.1	-0.181532291
-4.9	-0.200500533
-4.7	-0.212749629
-4.5	-0.217228915
-4.3	-0.213061846
-4.1	-0.199579783
-3.9	-0.176350297
-3.7	-0.143198957
-3.5	-0.100223779
-3.3	-0.047801725
-3.1	0.013413117
-2.9	0.082499769
-2.7	0.158288845
-2.5	0.239388858
-2.3	0.324219657
-2.1	0.411052079
-1.9	0.498052678
-1.7	0.583332241
-1.5	0.664996658
-1.3	0.741198604
-1.1	0.810188509
-0.9	0.870363233
-0.7	0.920310982
-0.5	0.958851077
-0.3	0.985067356
-0.1	0.998334166
0.1	0.998334166
0.3	0.985067356
0.5	0.958851077
0.7	0.920310982
0.9	0.870363233
1.1	0.810188509
1.3	0.741198604
1.5	0.664996658
1.7	0.583332241
1.9	0.498052678
2.1	0.411052079
2.3	0.324219657
2.5	0.239388858
2.7	0.158288845
2.9	0.082499769
3.1	0.013413117
3.3	-0.047801725
3.5	-0.100223779
3.7	-0.143198957
3.9	-0.176350297
4.1	-0.199579783
4.3	-0.213061846
4.5	-0.217228915
4.7	-0.212749629
4.9	-0.200500533
5.1	-0.181532291
5.3	-0.157031593
5.5	-0.128280059
5.7	-0.096611499
5.9	-0.063368926
6.1	-0.029862706
6.3	0.002668873
6.5	0.033095383
6.7	0.060425361
6.9	0.08383185
7.1	0.102671696
7.3	0.116498167
7.5	0.125066664
7.7	0.128333537
7.9	0.126448271
8.1	0.119739483
8.3	0.108695402
8.5	0.09393966
8.7	0.07620336
8.9	0.056294478
9.1	0.035065754
9.3	0.013382196
9.5	-0.007910644
9.7	-0.028016559
9.9	-0.046215747
10.1	-0.061888183
10.3	-0.074532603
10.5	-0.083780549
10.7	-0.089405142
10.9	-0.091324427
11.1	-0.089599332
11.3	-0.084426482
11.5	-0.076126276
11.7	-0.065126802
11.9	-0.051944295
12.1	-0.037160947
12.3	-0.021400959
12.5	-0.005305752
12.7	0.010490712
12.9	0.025385615
13.1	0.038829119
13.3	0.050343591
13.5	0.059539587
13.7	0.066128083
13.9	0.069928597
14.1	0.070873006
14.3	0.069005032
14.5	0.064475521
14.7	0.057533798
14.9	0.048515527
15.1	0.037827607
15.3	0.025930756
15.5	0.013320483
15.7	0.000507209
15.9	-0.012003684
16.1	-0.023731144
16.3	-0.034236336
16.5	-0.043138506
16.7	-0.05012825
16.9	-0.054977752
17.1	-0.057547661
17.3	-0.05779043
17.5	-0.055750057
17.7	-0.05155833
17.9	-0.045427772
18.1	-0.037641645
18.3	-0.028541453
18.5	-0.018512466
18.7	-0.007967862
18.9	0.002667867
19.1	0.012975613
19.3	0.022557791
19.5	0.031053327
19.7	0.038150935
19.9	0.043600206
20.1	0.047220127
20.3	0.048904749
20.5	0.048625844
20.7	0.046432499
20.9	0.042447729
21.1	0.036862283
21.3	0.029925943
21.5	0.021936698
21.7	0.013228233
21.9	0.004156275
22.1	-0.004915683
22.3	-0.0136307
22.5	-0.021652201
22.7	-0.028676754
22.9	-0.03444534
23.1	-0.0387527
23.3	-0.041454427
23.5	-0.042471576
23.7	-0.041792638
23.9	-0.039472865
24.1	-0.035630996
24.3	-0.030443563
24.5	-0.024137042
24.7	-0.016978175
24.9	-0.00926288
25.1	-0.001304198
25.3	0.006580237
25.5	0.01408072
25.7	0.020907478
25.9	0.026801725
26.1	0.031545326
26.3	0.034968732
26.5	0.036956892
26.7	0.037452949
26.9	0.0364596
27.1	0.034038111
27.3	0.030305051
27.5	0.02542691
27.7	0.01961284
27.9	0.013105829
28.1	0.006172675
28.3	-0.00090683
28.5	-0.007851075
28.7	-0.014387719
28.9	-0.020264268
29.1	-0.025257719
29.3	-0.029182928
29.5	-0.03189937
29.7	-0.033316063
29.9	-0.033394483