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Expression Matrix CSV-file

ℹ️ What is an expression matrix?

An expression matrix is a table where each row represents a measured feature - a gene, protein, or metabolite - and each column represents a sample. Each cell contains a numeric value reflecting the abundance of that feature in that sample.

How to format the expression matrix before uploading to Omics Studio

Your file must be a CSV file with:

Option A

  • One sample per row
  • One molecule ID per column

Option B

  • One molecule ID per row
  • One sample per column

Relevant for both options

  • Molecule IDs must be a valid (UniProt, Ensembl, CHEBI, or InChI). Only one type of ID can be used per file – mixing ID types is not allowed.
  • Each sample name must be unique and non-empty.
  • No empty cells in first row or column (besides A1).
  • There is no specific requriements for the first cell (A1). You can also leave it empty if preferred.

Example of option A

📄 Expression Matrix (.csv)
SampleA0A1B0GTW7H3BV60O14717...
Sample 110.14101678284929.931865492523076.69890691314978...
Sample 29.735649734286538.0856590575154212.5898915913406...
Sample 311.502122605212610.79568441760078.75086505276381...
Sample 410.14101678284929.931865492523076.69890691314978...

Example of option B

📄 Expression Matrix (.csv)
IDSample 1Sample 2Sample 3...
A0A1B0GTW710.14101678284929.7356497342865311.5021226052126...
H3BV609.931865492523078.0856590575154210.7956844176007...
O147176.6989069131497812.58989159134068.75086505276381...
P050675.954545218721247.860465052745394.87546291318788...

Expression values

  • Each expression value must be a number or the text NA.
  • Empty cells and NA are all treated as NaN values.
  • Any other text (e.g. missing, abc) will cause an error.
10.1410167828492NA6.69890691314978...
9.735649734286538.0856590575154212.5898915913406...
11.502122605212610.7956844176007...
NaN9.931865492523076.69890691314978...

💡 Good to know

✅ You can use both types of decimal separators (e.g. 10.53 or 10,53).
❌ Thousand separators are not allowed!