lionleaf / lionleaf/parallel-c-programs

introduction matrix.c is_sparse() function error

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Dominant language
C
Stars
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Forks
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Description

Probably nobody is paying attention to this repo..i was going to try a pull request but its very old.
anyways... is_sparse does not work correctly because the formula is inverted, see here to fix it:

54 //if((matrix.cols * matrix.rows)/zero_elements >= sparse_threshold){ <-- BAD
55 if((zero_elements/(matrix.cols * matrix.rows)) >= sparse_threshold){
return 1;
}else{
return 0;
}

also to get rid of warnings about printf''ing pointers change the %d to %p here:
186 // Attempting to multiply m and n, should work
187 error = matrix_multiply(m,n,&p);
188 printf("&p: %p\n",&p);
189 printf("p: %p\n",p);

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Research direction

Read matrix.c around lines 54-55 and 186-189. Verify the sparse calculation against sparse_threshold and the pointer format specifiers, then compile the relevant program to confirm the warning is gone and the reported behavior is corrected.

Written by the indexing model from the issue text.

Assessment

Tech stack
c
Domain
distributed-systems
Issue type
Bug
Difficulty
2/5
Estimated time
1-3 hours
Activity status
Stale
Clarity
Clearly specified
Newbie friendliness
45/100

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