fix deprecated NumPy issues that were causing CI errors

Author: murrayrm

examples/cds110-L8a_maglev-limits.ipynb

@@ -253,7 +253,7 @@
     "omega = np.linspace(0, 1e6, 100000)\n",
     "for name, sys in zip(['C1', 'C2', 'C3'], [magS1, magS2, magS3]):\n",
     "    freqresp = ct.frequency_response(sys, omega)\n",
-    "    bodeint = np.trapz(np.log(freqresp.magnitude), omega)\n",
+    "    bodeint = np.trapezoid(np.log(freqresp.magnitude), omega)\n",
     "    print(\"Bode integral for\", name, \"=\", bodeint)\n",
     "\n",
     "print(\"pi * sum[ Re(pk) ]\", pi * np.sum(magP.poles()[magP.poles().real > 0]))"

examples/cds112-L6_stochastic-linsys.ipynb

@@ -92,7 +92,7 @@
    "source": [
     "# Calculate the sample properties and make sure they match\n",
     "print(\"mean(V) [0.0] = \", np.mean(V))\n",
-    "print(\"cov(V) * dt [%0.3g] = \" % Q, np.round(np.cov(V), decimals=3) * dt)"
+    "print(\"cov(V) * dt [%0.3g] = \" % Q.item(), np.round(np.cov(V), decimals=3) * dt)"
    ]
   },
   {