title: Variable Missing with no defaults
body: <p>Hello I have a sample data set that I am trying to create a function to find wind chill for.This is the set:</p>
  <pre><code>       HighTemp WindSpeed Snowfall
  1-Jan        19         8      0.0
  2-Jan
  3-Jan        25         9      0.0
  4-Jan        33        14      7.6
  5-Jan        38         7      0.0
  6-Jan        34         6      2.1
  7-Jan        35        12      0.0
  8-Jan        27        15      0.0
  9-Jan        28        11      3.3
  10-Jan       30        17      1.4
  11-Jan       36        13      0.0
  12-Jan       44         9      0.0
  13-Jan       41         8      0.0
  14-Jan       34        14      0.0
  15-Jan       31        15      0.0
  16-Jan       32        12      2.8
  17-Jan       35        18      0.0
  18-Jan       20        22      0.0
  19-Jan       17        24      0.0
  20-Jan       16        20      0.6
  21-Jan       19         8      0.0
  22-Jan       25         9      0.0
  23-Jan       28        13     14.9
  24-Jan       23        11      0.0
  25-Jan       28        32      0.0
  26-Jan       33        13      0.0
  27-Jan       31        15      3.7
  28-Jan       39        10      0.0
  29-Jan       36         4      0.0
  30-Jan       33         8      0.9
  31-Jan       37        10      0.0
  </code></pre>
  <p>I am trying to create a function that executes this equation for each date of the month:</p>
  <p>Wind Chill= 35.74+0.6215Ta-35.75v^0.16+0.4275TaV^0.16
  Where Ta= HighTemp and V= WindSpeed</p>
  <p>The code I've written is:</p>
  <pre><code>wind_chill&lt;-function(HighTemp,WindSpeed){
  twc&lt;-(35.74)+(0.6215)*(HighTemp)-(35.75)*(WindSpeed)^0.16+(0.4275)*(HighTemp*WindSpeed)^0.16
  return(twc)
  }
  
  wind_chill(jan_weather)
  </code></pre>
  <p>But it returns an error reading WindSpeed is missing with no defaults.
  Please help I'm very new to this and just cannot figure this out.</p>