pivot heldout csv

eval-logs/pivot_heldout_1782710967.csv

@@ -15,3 +15,4 @@ ts_unix_s,elapsed_s,phase,docs,tokens,chars,warmup_docs_target,vocab_size,merges
 1782711438,430.454,train,2800,1498361,3848231,500,1056,800,3451.76,3480.89,6.505,1052.605343,1046.751610,6.959024,6.954247,10.039749,3.909113,3.895253,0.395655,573120.0,0.999737,0.999460,1.000000,1.000000,4.999046,5.733872,5.001927,4.998295,4.996583,4.999555,4.996262,0.016441,65.131268,84.301634,10.658074
 1782711469,461.162,train,3000,1604948,4122770,500,1056,800,3470.96,3480.23,6.505,1052.288509,1047.345969,6.958723,6.954491,10.039315,3.908192,3.894255,0.397855,573120.0,0.999725,0.999520,1.000000,1.000000,4.997821,5.636593,4.997724,4.997219,4.996047,4.998012,4.995195,0.015276,66.970298,87.067011,10.658074
 1782711501,492.682,train,3200,1714394,4402952,500,1056,800,3472.31,3479.72,6.495,1052.138330,1047.759646,6.958580,6.956487,10.039109,3.908966,3.895084,0.398011,573120.0,0.999696,0.999440,1.000000,1.000000,4.996079,5.642889,4.997908,4.998556,4.996458,4.997379,4.997184,0.001799,68.851118,89.914718,10.658074
+1782711532,524.298,train,3400,1824077,4682420,500,1056,800,3469.15,3479.08,6.485,1051.890937,1046.928972,6.958345,6.954669,10.038769,3.910689,3.896912,0.397648,573120.0,0.999679,0.999360,1.000000,1.000000,4.998945,5.793175,4.996347,4.998503,4.996268,4.998590,4.996309,0.022434,70.767204,92.831694,10.658074