Running xhmm to "Filters samples and targets and then mean-centers the targets" as follows results in the error posted in the question. Not sure what this is referring to?
xhmm --matrix -r group1.DATA.sample_interval_summary --centerData --centerType target -o DATA.filtered_centered.RD.txt --outputExcludedTargets DATA.filtered_centered.RD.txt.filtered_targets.txt --outputExcludedSamples ./DATA.filtered_centered.RD.txt.filtered_samples.txt --minTargetSize 10 --maxTargetSize 10000 --minMeanTargetRD 10 --maxMeanTargetRD 500 --minMeanSampleRD 25 --maxMeanSampleRD 200 --maxSdSampleRD 150