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CS 219 Administrivia:
Sep 30, 2009
CS 219 Administrivia:
Sep 30, 2009
•
Course web site:
www.cs.ucsb.edu/~gilbert/cs290
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Join the email (Google) discussion group!!
(see web site)
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Homework 1 is due next Wednesday (see web site)
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Reading in Davis:
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Review Ch 1 (definitions)
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Skim Ch 2 (you don't have to read all the code in detail)
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Read Chapter 3 (sparse triangular solves)
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Roxanne in HFH 5102 has a few copies of Davis for sale
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View Full Document Compressed Sparse Matrix Storage
Compressed Sparse Matrix Storage
•
Full storage:
•
2dimensional array.
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(nrows*ncols) memory.
31
0
53
0
59
0
41
26
0
31
41
59
26
53
1
3
2
3
1
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Sparse storage:
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Compressed storage by
columns
(CSC).
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Three 1dimensional arrays.
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(2*nzs + ncols + 1) memory.
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Similarly,
CSR.
1
3
5
6
value:
row:
colstart:
Matrix – Matrix Multiplication:
C = A * B
Matrix – Matrix Multiplication:
C = A * B
C(:, :) = 0;
for i = 1:n
for j = 1:n
for k = 1:n
C(i, j) = C(i, j) + A(i, k) * B(k, j);
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The n
3
scalar updates can be done in any order.
•
Six possible algorithms:
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This note was uploaded on 12/27/2011 for the course CMPSC 290h taught by Professor Chong during the Fall '09 term at UCSB.
 Fall '09
 Chong

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