(INFO
". Untiling an array means spliting two axes, permuting the slow parts "
"of those axes to be adjecent in the axis ordering, and then merging "
"them. This increases the dimension by one. Undoing a \"unu tile\" "
"uses the same \"-s\" argument, and sometimes a different \"-a\" argument, "
"as demonstrated here for a 3-D array:\n "
"\"unu untile -a 2 0 1\" undoes \"unu tile -a 2 0 1\"\n "
"\"unu untile -a 1 0 1\" undoes \"unu tile -a 1 0 2\"\n "
"\"unu untile -a 0 0 1\" undoes \"unu tile -a 0 1 2\". ")