Network & Matrix Computations

David Gleich

Purdue University

Fall 2011

Course number CS 59000-NMC

Tuesdays and Thursday, 10:30am-11:45am

CIVL 2123

In-class quiz 4

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CS 59000-NMC, 6 September

Please answer the following questions. You may not use any outside references or technology. Justify and explain all answers. This quiz is for my own evaluation, so that I can provide better instruction in the course.

Question

Let $\mA$ be a binary matrix. Suppose this matrix is composed of mostly ones and that the zeros are stored with a compressed-sparse row data structure. Write down an algorithm to compute $\vy = \mA \vx$ give the compressed sparse row data structure for $\mA$’s zeros in the arrays pointer and columns