)]}'
{
  "commit": "0bbb48a941993f5b5cb9b793d3e072e9fbb6076f",
  "tree": "9f020708a8b6169ad6e77c95ff2d5a605a363bf0",
  "parents": [
    "22b26cd7b75c678eff28557f2d3a862c635bb63e"
  ],
  "author": {
    "name": "Mike Vitus",
    "email": "mike@hidof.com",
    "time": "Tue Jul 08 15:11:22 2014 -0700"
  },
  "committer": {
    "name": "Mike Vitus",
    "email": "mike@hidof.com",
    "time": "Fri Jul 11 14:42:48 2014 -0700"
  },
  "message": "Adds support for computing the covariance using Eigen\u0027s sparse QR module.\n\nFor smaller problems Eigen is faster than SuiteSparseQR. This has been\ntested with Eigen 3.2.1. Below are detailed timings. Problem 1 is the\nsmallest and problem 3 is the largest. The timings below are:\nmean +- standard deviation.\n\nProblem 1:\nEigen       0.0009218 +- 0.0002755\nSuiteSparse 0.001406 +- 0.001610\n\nProblem 2:\nEigen       0.002338 +- 0.001005\nSuiteSparse 0.001910 +- 0.0004513\n\nProblem 3:\nEigen       0.005455 +- 0.001759\nSuiteSparse 0.002411 +- 0.0004974\n\nDetailed problem descriptions:\n\nProblem 1 size:\n                               Original                  Reduced\nParameter blocks                533                       54\nParameters                      368                      104\nEffective parameters           1201                       94\nResidual blocks                 233                       77\nResidual                       1194                      258\n\nProblem 2 size:\n                              Original                  Reduced\nParameter blocks                573                       84\nParameters                     1458                      184\nEffective parameters           1281                      164\nResidual blocks                 263                      107\nResidual                       1314                      378\n\nProblem 3 size:\n                              Original                  Reduced\nParameter blocks                613                      114\nParameters                     1548                      264\nEffective parameters           1361                      234\nResidual blocks                 293                      137\nResidual                       1434                      498\n\nChange-Id: I884a67e2f728fe2992812148d82ccf5f27864fd7\n",
  "tree_diff": [
    {
      "type": "modify",
      "old_id": "158e05962114eaee64673d0cbbcbcc2f757d2d2e",
      "old_mode": 33188,
      "old_path": "include/ceres/types.h",
      "new_id": "ba31236a425db7e8d854e65c4d5ddd5b63621f4c",
      "new_mode": 33188,
      "new_path": "include/ceres/types.h"
    },
    {
      "type": "modify",
      "old_id": "75c80bf5687b47ee39d7651b20ef8cd994337566",
      "old_mode": 33188,
      "old_path": "internal/ceres/covariance_impl.cc",
      "new_id": "437a03db582de321ef493b9714e0ec3bed435444",
      "new_mode": 33188,
      "new_path": "internal/ceres/covariance_impl.cc"
    },
    {
      "type": "modify",
      "old_id": "0e7e21730793a88b7f95b8ef284bfd362c8ee712",
      "old_mode": 33188,
      "old_path": "internal/ceres/covariance_impl.h",
      "new_id": "ff640b9d6a1a5c009c646a43957c7014b6e45f11",
      "new_mode": 33188,
      "new_path": "internal/ceres/covariance_impl.h"
    },
    {
      "type": "modify",
      "old_id": "471b2236dbe144fb7947b6821aa480692c8a3fc2",
      "old_mode": 33188,
      "old_path": "internal/ceres/covariance_test.cc",
      "new_id": "6de3fecd42236c2069009b876baa7be4a8dd0529",
      "new_mode": 33188,
      "new_path": "internal/ceres/covariance_test.cc"
    }
  ]
}