Hi, I'm playing with spherical harmonic (special.sph_harm()) and I don't understand what I get.

From Wolfram (http://mathworld.wolfram.com/SphericalHarmonic.html), Re_Y11.png, Im_Y11.png & mod_Y11.png seems to be correct

http://fredantispam.free.fr/Re_Y11.png http://fredantispam.free.fr/Im_Y11.png http://fredantispam.free.fr/mod_Y11.png when I use r = (sqrt((2*n+1)/4.0/pi)*exp(0.5*(gammaln(n-m+1)-gammaln(n+m+1)))*sin(phi)*exp(1j*m*theta))**2 But when I use special.sph_harm(m,n,theta,phi), I get this http://fredantispam.free.fr/Re_Y11_2.png http://fredantispam.free.fr/Im_Y11_2.png http://fredantispam.free.fr/mod_Y11_2.png Real & imaginary parts don't seem to be correct. What I'm doing wrong ? Cheers, Here the small code I have used. from sys import argv from scipy import pi, cos, sin, exp, sqrt, mgrid, real, imag from scipy.special import sph_harm, gammaln from enthought.tvtk.tools import mlab, ivtk def main(): m = int(argv[1]) n = int(argv[2]) gui = mlab.GUI() window = ivtk.IVTKWithCrustAndBrowser(size=(1175,773)) window.open() fig = mlab.Figure(window.scene) o = mlab.Outline() fig.add(o) dphi, dtheta = pi/180, pi/180 [phi, theta] = mgrid[0:pi+dphi:dphi, 0:2*pi+dtheta:dtheta] ### cf. Wolfram : theta <--> phi r = real(sph_harm(m,n,theta,phi))**2 # r = real(sqrt((2*n+1)/4.0/pi)*exp(0.5*(gammaln(n-m+1)-gammaln(n+m+1)))*sin(phi)*exp(1j*m*theta))**2 x = r*cos(theta)*sin(phi) y = r*sin(theta)*sin(phi) z = r*cos(phi) s = mlab.Surf(x, y, z, z) fig.add(s) window.scene.x_plus_view() window.scene.camera.parallel_projection = True window.scene.camera.azimuth(-62) window.scene.camera.elevation(19.5) gui.start_event_loop() if __name__ == '__main__': main() -- Fred.