How to Convert Magnitude(g/N)/Phase (degrees) data in to Complex Receptance (m/N)

I have an experimental data as shown below. The data was provided in Magnitude and Phase format. The magnitude (Accelerance) is in g/N and Phase is in degrees. I have been trying to convert this in to Complex Receptance data in m/N.

How can I convert this data in to Complex format (Real & Imaginary)?

X_Value Y_Module Y_Phase

Hz (g)/(N) °

0.00000e+000 1.16597e+002 -1.80000e+002

3.12500e-001 9.33462e+001 5.02240e+001

6.25000e-001 5.64734e+001 -5.00929e+001

9.37500e-001 6.46840e+001 -1.31199e+002

1.25000e+000 7.82452e+001 1.24086e+002

1.56250e+000 7.76202e+001 2.68690e+001

1.87500e+000 9.72691e+001 -5.02411e+001

2.18750e+000 4.28383e+002 -1.46419e+002

2.50000e+000 1.53160e+002 2.92812e+001

2.81250e+000 9.49255e+001 -3.97049e+001

3.12500e+000 9.55640e+001 -1.13590e+002

3.43750e+000 9.40966e+001 1.67688e+002

3.75000e+000 8.98931e+001 1.00578e+002

4.06250e+000 1.25336e+002 4.60492e+001

4.37500e+000 2.65255e+002 -2.52481e+001

4.68750e+000 6.70180e+002 -1.13068e+002

5.00000e+000 3.86090e+003 1.56183e+002

Answer 1

[Chunru]

x =[0.00000e+000	1.16597e+002	    -1.80000e+002	
 3.12500e-001	        9.33462e+001        5.02240e+001	
 6.25000e-001	        5.64734e+001        -5.00929e+001	
 9.37500e-001	        6.46840e+001	    -1.31199e+002	
 1.25000e+000	7.82452e+001	     1.24086e+002	
 1.56250e+000	7.76202e+001	     2.68690e+001	
 1.87500e+000	9.72691e+001	    -5.02411e+001	
 2.18750e+000	4.28383e+002    -1.46419e+002	
 2.50000e+000	1.53160e+002	     2.92812e+001	
 2.81250e+000	9.49255e+001	    -3.97049e+001	
 3.12500e+000	9.55640e+001	    -1.13590e+002	
 3.43750e+000	9.40966e+001	     1.67688e+002	
 3.75000e+000	8.98931e+001	     1.00578e+002	
 4.06250e+000	1.25336e+002	     4.60492e+001	
 4.37500e+000	2.65255e+002	    -2.52481e+001	
 4.68750e+000	6.70180e+002	    -1.13068e+002	
 5.00000e+000	3.86090e+003	     1.56183e+002];

r = x(:,2).*exp(1i*deg2rad(x(:, 3)))

r = 
   1.0e+03 *

  -0.1166 - 0.0000i
   0.0597 + 0.0717i
   0.0362 - 0.0433i
  -0.0426 - 0.0487i
  -0.0439 + 0.0648i
   0.0692 + 0.0351i
   0.0622 - 0.0748i
  -0.3569 - 0.2369i
   0.1336 + 0.0749i
   0.0730 - 0.0606i
  -0.0382 - 0.0876i
  -0.0919 + 0.0201i
  -0.0165 + 0.0884i
   0.0870 + 0.0902i
   0.2399 - 0.1131i
  -0.2626 - 0.6166i
  -3.5321 + 1.5591i

[Vivek E K]

Thanks for the reply. The complex data in your code is the accelerance data. To get the displacement I need to integrate it twice. How can I include the integration to this code and get the receptance (Displacement) complex data?

[Walter Roberson]

receptance = cumtrapz(x, cumtrapz(x, r));

Warning! Getting displacement by numeric integration of acceleration data is notoriously error prone !! A lot of the time you end up needing to smooth the data before integrating -- but smoothing requires that you have a model for the "jerk" (derivative of acceleration) or you can just end up making things worse,

[Vivek E K]

Thanks for your reply @Walter Roberson. Is there any other reliable method to get the receptance from the accelerance data?

[Walter Roberson]

https://www.researchgate.net/post/How_can_I_calculate_displacement_from_accelerometer_data has some discussion.