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(Figure 7.4) to download the metadata text file. Open the file in a spreadsheet, remove all

columns except “run”, “group”, and “time”. Then, rename “run” to “SampleID”, insert a

data type row as shown in Figure 7.5, and save the file as a TSV file with the name: “data/

sample-metadata.tsv”.

If you have EDirect installed on your computer, you can search the NCBI database and

retrieve metadata from it. EDirect is a collection of Linux-based command-line E-Utilities

programs. The instructions for installing EDirect programs are available at the NCBI

FIGURE 7.5  The sample metadata text file “sample-metadata.tsv”.

FIGURE 7.4  Downloading metadata from SRA database using Run Selector.