Update README.md

README.md

@@ -40,7 +40,7 @@ para.resample  = true;
    * .beta : Parameter for thresholding. (default 1/(2*nthroot(m\*n,4)))
    * .gamma : Parameter for desired convergence rate. Value should between 0 and 1. Turn this parameter bigger will slow the convergence speed but tolerate harder problem, such as higher $\alpha$, $r$ or $\mu$. (default 0.7)   
    * .mu : Incoherence of underlying low rank matrix. Input can be in format of .mu = mu_max, or .mu = [mu_U, mu_V]. (default 5) 
-   * .con : constant for row/column samples. $con\*r\*\log(m)$ rows and $con\*r\*\log(n)$ columns will be sampled. (default 4)
+   * .con : constant $c$ for row/column samples. $c\*r\*\log(m)$ rows and $c\*r\*\log(n)$ columns will be sampled. (default 4)
    * .resample : Whether the program resamples the rows and columns every iteration. (default true)
 
 ## Output Description