| Feature | Mathcad 13 | Mathcad 12 | Mathcad 11 |
| Determinant Operator | Right-click to select the algorithm. | Right-click to select the algorithm. | Determinant/absolute value operator autodetects shape of argument. |
| Calculation Speed of Programs Creating Large Matrices | Preallocating matrices is recommended in programs. | Preallocating matrices is required in programs. | Preallocating matrices is recommended in programs. |
| Solve Blocks Find Whole Vectors | Solve blocks only solve for whole vector or use scalar parameters. | Solve blocks only solve for whole vector or use scalar parameters. | Solve blocks can solve for single element of a vector; results are misleading. |
| Simultaneous versus Sequential Multiple Array Assignments | Array assignments of interdependent variables are evaluated simultaneously. A worksheet compatibility switch exists to change the behaviour to match Mathcad 11. | Array assignments of interdependent variables are evaluated simultaneously. | Array assignments of interdependent variables are evaluated sequentially. |
| Arrays Elements Must Exist Before They Can Be Referenced | Undefined array elements cannot be used in any context. Assign the last desired element to zero-pad the array. | Undefined array elements cannot be used in any context. Assign the last desired element to zero-pad the array. | Assigning an indexed array to itself for undefined elements zero-pads the array. |
| Matrices Cannot Contain Functions and Scalars | Mathcad array elements must be either values or functions, and functions must have the same signature. | Mathcad array elements must be either values or functions, and functions must have the same signature. | Any Mathcad types can be mixed as array elements. |
| Singular Value Functions Replaced | The svd2 function packs results into a single nested vector, making it easier to use results. | The svd and svds functions find U, V and singular value vector, respectively. | The svd and svds functions find U, V and singular value vector, respectively. |
