Troubleshooting and limits

"Cannot edit in read-only mode"

h5v only writes when the file is opened with -w:

h5v -w file.h5

If you forget -w, edit actions report that the file must be reopened in write mode.

An image dataset does not render as an image

Check the image metadata:

• CLASS must be IMAGE
• IMAGE_SUBCLASS must be a supported image subclass
• truecolor and indexed images also need INTERLACE_MODE

See Image conventions.

The UI is blank or badly garbled

Try:

h5v --no-terminal-graphics file.h5

If the terminal also struggles with richer symbols or line drawing:

h5v --compatibility file.h5

Compatibility mode switches to simpler symbols and text/braille fallbacks. Multichart also falls back to a terminal-native braille plot.

See Installation for persistent compatibility settings.

A compound dataset does not show in matrix mode

That is expected for the compound container itself. The root node shows a schema preview. Drill down to a projected leaf field for preview or matrix rendering.

Large fixed strings look truncated

Fixed strings are read with a 32768 byte cap.

Very large previews are chunked

Chart previews are segmented with a maximum segment size of 250000 elements. Use PageUp and PageDown to move through the data.

A numeric preview fails to render bounds

If the current slice contains only invalid numeric values such as NaN or infinity, h5v cannot compute chart bounds.

Very wide or tall images

If an image is much wider or taller than the content pane, h5v may switch to a pannable windowed view instead of shrinking it aggressively.

Use /images/wide_grayscale from the bundled example file to test this path.