testlist <- list(col = c(735007472L, -1200343012L, 1656197827L, -501651612L,  357438625L, -1286554371L, -38967632L, 1355791995L, -1626313897L,  NA, 1527163453L, 521314869L, 1622595092L, 110301443L, 1081652112L,  1198656742L, -2106114553L, 464646007L, -1214663465L, -1420424180L,  -1281201906L, 1966151606L, -1446361359L, 1012062143L, -904542491L,  -944415618L, 1326536186L, 1734411892L, 1143376057L), N = -518773456L,      row = c(326282000L, -2072327370L, -2072327370L, -1880788522L,      520532224L, 1535731267L, -991354296L))
result <- do.call(propr:::coordToIndex,testlist)
str(result)