1. A computer system with a processor and a memory for handwritten mathematical expression recognition, the computer system comprising: a symbol grouping and recognition component configured to group input strokes corresponding to a handwritten mathematical expression into symbols and to recognize the symbols, based upon intra-group and inter-group information associated with the input strokes, the intra-group information associated with the input strokes includes a confidence representative of whether the input strokes are a certain symbol provided by the recognition of a symbol, and a score representative of whether the input strokes are a valid symbol based upon intra-group spatial information that includes a size difference among the input strokes and an offset measurement among the input strokes; and a tabular structure analysis component configured to determine whether at least one of the symbols corresponds to a tabular structure by dividing the grouped input strokes into rows and columns in accordance with a size of the tabular structure and indicating that the rows and columns correspond to a tabular structure when the tabular structure has a bracketing character to its left wherein the components are implemented as computer-executable instructions stored in the memory for execution by the processor.
1. A computer system with a processor and a memory for handwritten mathematical expression recognition, the computer system comprising: a symbol grouping and recognition component configured to group input strokes corresponding to a handwritten mathematical expression into symbols and to recognize the symbols, based upon intra-group and inter-group information associated with the input strokes, the intra-group information associated with the input strokes includes a confidence representative of whether the input strokes are a certain symbol provided by the recognition of a symbol, and a score representative of whether the input strokes are a valid symbol based upon intra-group spatial information that includes a size difference among the input strokes and an offset measurement among the input strokes; and a tabular structure analysis component configured to determine whether at least one of the symbols corresponds to a tabular structure by dividing the grouped input strokes into rows and columns in accordance with a size of the tabular structure and indicating that the rows and columns correspond to a tabular structure when the tabular structure has a bracketing character to its left wherein the components are implemented as computer-executable instructions stored in the memory for execution by the processor. 10. The computer system of claim 1 , further comprising a user interface component configured to receive the input strokes and to recognize candidates of the handwritten mathematical expression, wherein multiple recognized candidates are provided for selection at an expression level, a sub-expression level, and a symbol level, wherein mechanisms are provided for reviewing and correcting the recognized candidates.