title: Brace indexing error when using MATLAB cell2mat() function
body: <p>I can't understand why I'm suddenly getting an error even though I've used cell2mat in the same way for prior codes. The error reads</p>
  
  <pre><code>Brace indexing is not supported for variables of this type.
  Error in cell2mat
  cellclass = class(c{1});
  </code></pre>
  
  <p>And the corresponding code is</p>
  
  <pre><code>clear all;
  close all;
  clc;
  
  parta = xlsread('C:\Users\Zahin\Desktop\Fall 2018\MEC 516\Lab 9\Data.xlsx',1,'A3:R15');
  partb = xlsread('C:\Users\Zahin\Desktop\Fall 2018\MEC 516\Lab 9\Data.xlsx',2,'A3:K11');
  
  a_rg = cell2mat(parta(:,1));
  </code></pre>
  
  <p>My goal is to turn these cells into column vectors so that I can use the plot function. When I do something like:</p>
  
  <pre><code>plot(parta(:,1),parta(:,2));
  </code></pre>
  
  <p>MATLAB will create a line plot that connects each point in the order of the array element index (i.e., (x1,y1) to (x2,y2) even if (x3,y3) would be closer to (x1,y1) in a linear fit). I can't understand why this occurs, but I assume its related to the fact that I can't convert the table arrays. </p>