Convert TXT to GCT

What the TXT format is

.txt is a plain-text container with no fixed data structure. Notepad, TextEdit, code editors, spreadsheet programs, laboratory instruments, and game-code databases commonly create it. A TXT file may contain tab-separated data, comma-separated values, or human-readable cheat codes, so changing its filename to .gct does not perform a valid conversion.

What the GCT format is

GenePattern GCT is a tab-delimited matrix format used for gene-expression and other genomic datasets. It stores a version marker, row and column counts, sample names, feature identifiers, descriptions, and numeric values.

Nintendo Wii GCT is a compiled binary cheat-code file used by cheat loaders such as Gecko OS, USB Loader GX, and CFG Loader. It contains encoded code lines rather than ordinary readable data. These two formats are unrelated and cannot be interchanged.

How to convert TXT to GCT

For GenePattern GCT files

1. Open the TXT file in LibreOffice Calc, Microsoft Excel, or a code editor and determine its delimiter. GenePattern GCT requires tab-separated fields, not comma-separated fields.
2. Arrange the data with one feature per row and one sample per column. Use a first column for feature identifiers and a second column for descriptions; sample names begin in the third column.
3. Save or export the table as tab-delimited text, preserving UTF-8 encoding and decimal values.
4. Add the GCT header. For a matrix containing R data rows and C sample columns, the file must begin with:

#1.2
R	C
Name	Description	Sample1	Sample2

The second line counts feature rows and sample columns; it does not count the Name and Description fields. A minimal valid example is:

#1.2
2	2
Name	Description	Control	Treated
GeneA		4.2	5.1
GeneB		7.0	6.6

Save the result with a .gct extension, then validate it by loading it in GenePattern or another GCT-aware application. A small Python conversion for an already tab-delimited file can add the header:

import csv

src = "input.txt"
dst = "output.gct"

with open(src, newline="", encoding="utf-8") as f:
    rows = list(csv.reader(f, delimiter="\t"))

header, data = rows[0], rows[1:]
with open(dst, "w", newline="", encoding="utf-8") as f:
    w = csv.writer(f, delimiter="\t", lineterminator="\n")
    w.writerow(["#1.2"])
    w.writerow([len(data), max(0, len(header) - 2)])
    w.writerows(rows)

For Nintendo Wii cheat-code GCT files

1. Obtain cheat codes in a supported source format, such as a Gecko text file containing a game ID and hexadecimal code lines. Arbitrary prose or unrelated TXT data cannot be converted.
2. Open the source in a Wii-specific utility such as Wii Cheat Code Manager or Ocarina Code Manager. These programs parse code types, assemble the required binary representation, and write the GCT header.
3. Select the game, enable the desired codes, and use Export → GCT or the equivalent save command. Name the output gameid.gct, using the six-character game ID required by the loader.
4. Copy the file to the cheat directory expected by the loader, commonly /codes/ on an SD card, then enable cheats in the loader. The exact directory and filename rules depend on the loader and game region.

Do not use a generic online TXT converter for Wii codes. It will usually rename or re-encode the file without compiling the binary structure, and uploading cheat files can expose game identifiers or custom code.

Quality, compatibility, and limitations

GenePattern conversion preserves values only if the source delimiter, encoding, row labels, column labels, and decimal notation are interpreted correctly. Check for blank lines, duplicated feature names, embedded tabs, comma decimal separators, missing values, and formulas that were accidentally saved as displayed values. Keep the file UTF-8 and avoid spreadsheet date or scientific-notation changes when identifiers resemble numbers.

GenePattern GCT version #1.2 is the usual choice; some applications also support version #1.3 with additional metadata. Confirm the target program's specification before adding metadata or changing the header.

Wii GCT compatibility depends on the console region, game revision, code type, loader, and cheat-engine version. A successfully generated file can still fail if the codes target a different game ID or revision. GCT is not a compressed TXT format, so changing extensions or compressing the source does not create a usable file.