title: Terminating with uncaught exception of type NSException?
body: <p>My application crashes when clicking a button to go to segue into a new view. This comes up: </p>
  
  <pre><code>int main(int argc, char * argv[])
  {
      @autoreleasepool {
          return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
      }
  }
  </code></pre>
  
  <p>"return UIApplicationMain..." is highlighted in green with "Thread 1: Signal SIGABRT" at the end.
  The error also includes this in the output:</p>
  
  <pre><code>**Terminating app due to uncaught exception *** 'NSUnknownKeyException reason:'[&lt;SlopeViewController 0x8b68c70&gt; setValue:forUndefinedKey:]: this class is not key value        coding-compliant for the key m.' *** First throw call stack: (0x16b19b8 0x14328b6 0x17407c1   0x10f00ee 0x105c7db 0x105bd33 0x10be069 0x4b579b 0x14447d2 0x16acf5a 0x4b42f4 0x336e79 0x337491  0x337792 0x337c98 0x345912 0x345c5a 0x5aca79 0x34279a 0x3429a0 0x3429e0 0x73dd2b 0x72e181 0x72e1fc  0x1444874 0x2343b7 0x234343 0x32027e 0x320641 0x31f8fd 0x26fa0d 0x270266 0x245076 0x232efb 0x2ee332b  0x162d48d 0x162d3e5 0x162d11b 0x1657b30 0x165710d 0x1656f3b 0x35f5ff2 0x35f5e19 0x2304eb 0x6fd3  0x1d1370d 0x1)
  libc++abi.dylib: terminating with uncaught exception of type NSException
  (lldb
  </code></pre>
  
  <p>I have no idea what to do. Please help!</p>