unify CSRLinear, CSCLinear, COOLinear using SparseLinear
#258
| Job | Run time |
|---|---|
| 2m 1s | |
| 2m 43s | |
| 2m 8s | |
| 3m 22s | |
| 2m 24s | |
| 3m 13s | |
| 1m 53s | |
| 2m 27s | |
| 3m 11s | |
| 1m 46s | |
| 2m 25s | |
| 27m 33s |