diff --git a/examples/field-operations2.ipynb b/examples/field-operations2.ipynb
index 13b1a0c..143a33b 100644
--- a/examples/field-operations2.ipynb
+++ b/examples/field-operations2.ipynb
@@ -213,7 +213,7 @@
     "Emc = mc.compute(system.energy.zeeman.energy, system)\n",
     "print(f\"df: {Edf}\")\n",
     "print(f\"mc: {Emc}\")\n",
-    "print(f\"rerr: {abs(Edf-Emc)/Edf * 100} %\")"
+    "print(f\"rerr: {abs(Edf - Emc) / Edf * 100} %\")"
    ]
   },
   {
@@ -334,7 +334,7 @@
     "Emc = mc.compute(system.energy.uniaxialanisotropy.energy, system)\n",
     "print(f\"df: {Edf}\")\n",
     "print(f\"mc: {Emc}\")\n",
-    "print(f\"rerr: {abs(Edf-Emc)/Edf * 100} %\")"
+    "print(f\"rerr: {abs(Edf - Emc) / Edf * 100} %\")"
    ]
   },
   {
@@ -453,7 +453,7 @@
     "Emc = mc.compute(system.energy.exchange.energy, system)\n",
     "print(f\"df: {Edf}\")\n",
     "print(f\"mc: {Emc}\")\n",
-    "print(f\"rerr: {abs(Edf-Emc)/Edf * 100} %\")"
+    "print(f\"rerr: {abs(Edf - Emc) / Edf * 100} %\")"
    ]
   },
   {
@@ -572,7 +572,7 @@
     "Emc = mc.compute(system.energy.dmi.energy, system)\n",
     "print(f\"df: {Edf}\")\n",
     "print(f\"mc: {Emc}\")\n",
-    "print(f\"rerr: {abs(Edf-Emc)/Edf * 100} %\")"
+    "print(f\"rerr: {abs(Edf - Emc) / Edf * 100} %\")"
    ]
   },
   {