i’m trying to do a PET experiment in my university lab. I’m using the iradon and iradonsart function from the scikit package to reconstruct the position of my point like source. My problem is that the image the two functions return seem to me that have x and y axis swap. Could it be due to the definition of my sinogram or it is due to something else?

This is the code i use:

Definition of the sinogram with the data i measured:

n_bins =80

phi = np.array([90,90,90,90,90, 80,80,80,80,80, 60,60,60, 40,40,40,  20,20,20,  0,0,0, -20,-20,-20, -40,-40,-40 ,-60,-60,-60, -80,-80,-80,])
s = np.array([7.7,7.2,6.7,6.2,5.7, 7.2,6.7,6.2,5.7,5.2, 5.3,4.8,4.3, 2.85,2.35,1.85, 1,0.5,0,  -1.4,-1.9,-2.4, -3.5,-4,-4.5, -5.2,-5.7,-6.2, -6.25,-6.75,-7.25, -6.4,-6.9,-7.4])
err= np.array([0.16,2.31,3.31,1.85,0.66,  0.64,2.2,2.91,1.45,0.22,  1.46,3.05,1.90,  1.91,2.76,2.03, 1.83,2.73,2.17, 1.76,2.95,2.29, 2.61,2.73,1.64, 1.85,3.16,1.80, 2.04,3.16,1.65, 2.57,3.09,1.42])

sinogram , xax , yax , imagesinogram = plt.hist2d(s,phi ,bins= n_bins ,range= [[-20,20],[-90,90]], weights=err, cmap=plt.cm.Greens , cmin=None , cmax=None)

Iradon function:

recostruction_fbp = iradon ( sinogram , theta=None , output_size =80, filter_name="shepp-logan", interpolation ="cubic" , circle=False)

iradon_sart function:

reconstruction_sart=iradon_sart(sinogram , theta=None,)

Thanks for the help