Merge pull request #1 from NanoComp/master

sync docs with meep main

doc/docs/Python_Tutorials/Basics.md

@@ -572,31 +572,6 @@ wvl = f[:,1]
 # create a 2d matrix for the wavelength by repeating the column vector for each angle
 wvls = np.matlib.repmat(np.reshape(wvl, (wvl.size,1)),1,theta_in.size)
 
-plt.figure()
-plt.pcolormesh(kxs, wvls, Rmeep, cmap='hot', shading='gouraud', vmin=0, vmax=Rmeep.max())
-plt.axis([kxs[0,0], kxs[0,-1], wvl[-1], wvl[0]])
-plt.yticks([t for t in np.arange(0.4,0.9,0.1)])
-plt.xlabel("Bloch-periodic wavevector ($k_x/2π$)")
-plt.ylabel("wavelength (μm)")
-plt.title("reflectance (meep)")
-cbar = plt.colorbar()
-cbar.set_ticks([t for t in np.arange(0,0.4,0.1)])
-cbar.set_ticklabels(["{:.1f}".format(t) for t in np.arange(0,0.4,0.1)])
-plt.show()
-
-plt.figure()
-plt.pcolormesh(thetas, wvls, Rmeep, cmap='hot', shading='gouraud', vmin=0, vmax=Rmeep.max())
-plt.axis([thetas.min(), thetas.max(), wvl[-1], wvl[0]])
-plt.xticks([t for t in range(0,100,20)])
-plt.yticks([t for t in np.arange(0.4,0.9,0.1)])
-plt.xlabel("angle of incident planewave (degrees)")
-plt.ylabel("wavelength (μm)")
-plt.title("reflectance (meep)")
-cbar = plt.colorbar()
-cbar.set_ticks([t for t in np.arange(0,0.4,0.1)])
-cbar.set_ticklabels(["{:.1f}".format(t) for t in np.arange(0,0.4,0.1)])
-plt.show()
-
 n1=1
 n2=3.5
 
@@ -606,25 +581,62 @@ theta_out = lambda theta_in: math.asin(n1*math.sin(theta_in)/n2)
 
 # compute Fresnel reflectance for P-polarization in medium n2
 # for incident planewave in medium n1 at angle theta_in
-Rfresnel = lambda theta_in: math.fabs((n1*math.cos(theta_out(theta_in))-n2*math.cos(theta_in))/(n1*math.cos(theta_out(theta_in))+n2*math.cos(theta_in)))**2
+Rfresnel = lambda theta_in: math.fabs((n1*math.cos(theta_out(theta_in)) -
+                                       n2*math.cos(theta_in)) /
+                                      (n1*math.cos(theta_out(theta_in)) +
+                                       n2*math.cos(theta_in)))**2
 
 Ranalytic = np.empty((50, theta_in.size))
 for m in range(wvl.size):
     for n in range(theta_in.size):
         Ranalytic[m,n] = Rfresnel(math.radians(thetas[m,n]))
 
-plt.figure()
-plt.pcolormesh(thetas, wvls, Ranalytic, cmap='hot', shading='gouraud', vmin=0, vmax=Ranalytic.max())
-plt.axis([thetas.min(), thetas.max(), wvl[-1], wvl[0]])
-plt.xticks([t for t in range(0,100,20)])
-plt.yticks([t for t in np.arange(0.4,0.9,0.1)])
-plt.xlabel("angle of incident planewave (degrees)")
-plt.ylabel("wavelength (μm)")
-plt.title("reflectance (analytic)")
-cbar = plt.colorbar()
-cbar.set_ticks([t for t in np.arange(0,0.4,0.1)])
-cbar.set_ticklabels(["{:.1f}".format(t) for t in np.arange(0,0.4,0.1)])
-plt.show()
+fig, axs = plt.subplots(nrows=2, ncols=2, figsize=(9,6))
+
+wvl_idx = 0
+axs[0, 0].plot(theta_in,Rmeep[wvl_idx,:], 'bo-', label="meep")
+axs[0, 0].plot(theta_in,Ranalytic[wvl_idx,:], 'ro-', label="analytic")
+axs[0, 0].set_xlabel("angle of incident planewave (degrees)")
+axs[0, 0].set_ylabel(f"reflectance at $\lambda$ = {wvl[wvl_idx]:.1f} μm")
+axs[0, 0].legend()
+
+pc = axs[0, 1].pcolormesh(kxs, wvls, Rmeep, cmap='hot_r', shading='gouraud',
+                          vmin=0, vmax=Rmeep.max())
+axs[0, 1].axis([kxs[0,0], kxs[0,-1], wvl[-1], wvl[0]])
+axs[0, 1].set_yticks([t for t in np.arange(wvl[-1], wvl[0] + 0.1, 0.1)])
+axs[0, 1].set_xlabel("Bloch-periodic wavevector ($k_x/2π$)")
+axs[0, 1].set_ylabel("wavelength (μm)")
+axs[0, 1].set_title("reflectance (meep)")
+cbar = fig.colorbar(pc, ax=axs[0, 1])
+cbar.set_ticks([t for t in np.arange(0, 0.4, 0.1)])
+cbar.set_ticklabels(["{:.1f}".format(t) for t in np.arange(0, 0.4, 0.1)])
+
+pc = axs[1, 0].pcolormesh(thetas, wvls, Rmeep, cmap='hot_r', shading='gouraud',
+                          vmin=0, vmax=Rmeep.max())
+axs[1, 0].axis([thetas.min(), thetas.max(), wvl[-1], wvl[0]])
+axs[1, 0].set_xticks([t for t in range(0,100,20)])
+axs[1, 0].set_yticks([t for t in np.arange(wvl[-1], wvl[0] + 0.1, 0.1)])
+axs[1, 0].set_xlabel("angle of incident planewave (degrees)")
+axs[1, 0].set_ylabel("wavelength (μm)")
+axs[1, 0].set_title("reflectance (meep)")
+cbar = fig.colorbar(pc, ax=axs[1, 0])
+cbar.set_ticks([t for t in np.arange(0, 0.4, 0.1)])
+cbar.set_ticklabels(["{:.1f}".format(t) for t in np.arange(0, 0.4, 0.1)])
+
+pc = axs[1, 1].pcolormesh(thetas, wvls, Ranalytic, cmap='hot_r', shading='gouraud',
+                          vmin=0, vmax=Ranalytic.max())
+axs[1, 1].axis([thetas.min(), thetas.max(), wvl[-1], wvl[0]])
+axs[1, 1].set_xticks([t for t in range(0,100,20)])
+axs[1, 1].set_yticks([t for t in np.arange(wvl[-1], wvl[0] + 0.1, 0.1)])
+axs[1, 1].set_xlabel("angle of incident planewave (degrees)")
+axs[1, 1].set_ylabel("wavelength (μm)")
+axs[1, 1].set_title("reflectance (analytic)")
+cbar = fig.colorbar(pc, ax=axs[1, 1])
+cbar.set_ticks([t for t in np.arange(0, 0.4, 0.1)])
+cbar.set_ticklabels(["{:.1f}".format(t) for t in np.arange(0, 0.4, 0.1)])
+
+fig.tight_layout()
+fig.savefig('reflectance_angular_spectrum.png', bbox_inches='tight', dpi=150)
 ```
 
 ![](../images/reflectance_angular_spectrum.png#center)