qax-os/excelize · error

cannot set both 'Formula' and 'Paragraph' for chart title

Error message

cannot set both 'Formula' and 'Paragraph' for chart title

What it means

ErrChartTitle is returned when a chart's Title options set both Formula (a cell-reference-driven title) and Paragraph (rich-text runs) at the same time. A chart title can have exactly one source of content, so parseTitle rejects the ambiguous combination up front.

Source

Thrown at errors.go:34

	"fmt"
	"strings"
)

var (
	// ErrAddVBAProject defined the error message on add the VBA project in
	// the workbook.
	ErrAddVBAProject = errors.New("unsupported VBA project")
	// ErrAttrValBool defined the error message on marshal and unmarshal
	// boolean type XML attribute.
	ErrAttrValBool = errors.New("unexpected child of attrValBool")
	// ErrCellCharsLength defined the error message for receiving a cell
	// characters length that exceeds the limit.
	ErrCellCharsLength = fmt.Errorf("cell value must be 0-%d characters", TotalCellChars)
	// ErrCellStyles defined the error message on cell styles exceeds the limit.
	ErrCellStyles = fmt.Errorf("the cell styles exceeds the %d limit", MaxCellStyles)
	// ErrChartTitle defined the error message on both formula and rich text for
	// chart title.
	ErrChartTitle = errors.New("cannot set both 'Formula' and 'Paragraph' for chart title")
	// ErrColumnNumber defined the error message on receive an invalid column
	// number.
	ErrColumnNumber = fmt.Errorf("the column number must be greater than or equal to %d and less than or equal to %d", MinColumns, MaxColumns)
	// ErrColumnWidth defined the error message on receive an invalid column
	// width.
	ErrColumnWidth = fmt.Errorf("the width of the column must be less than or equal to %d characters", MaxColumnWidth)
	// ErrCoordinates defined the error message on invalid coordinates tuples
	// length.
	ErrCoordinates = errors.New("coordinates length must be 4")
	// ErrCustomNumFmt defined the error message on receive the empty custom
	// number format.
	ErrCustomNumFmt = errors.New("custom number format can not be empty")
	// ErrDataValidationFormulaLength defined the error message for receiving a
	// data validation formula length that exceeds the limit.
	ErrDataValidationFormulaLength = fmt.Errorf("data validation must be 0-%d characters", MaxFieldLength)
	// ErrDataValidationRange defined the error message on set decimal range
	// exceeds limit.
	ErrDataValidationRange = errors.New("data validation range exceeds limit")

View on GitHub (pinned to f2483381fb)

Solutions

1. Keep only one of Formula or Paragraph set in ChartTitle
2. If you want the title driven by a cell, clear the Paragraph slice and set Formula
3. If you want static rich text, clear Formula and keep the Paragraph runs
4. Guard your chart-config builder so it errors before calling AddChart when both are non-empty

Example fix

// before
Title: ChartTitle{Formula: "Sheet1!$A$27", Paragraph: []RichTextRun{{Text: "Column Chart"}}}
// after
Title: ChartTitle{Paragraph: []RichTextRun{{Text: "Column Chart"}}}

if len(t.Paragraph) > 0 && t.Formula != "" {
    return errors.New("chart title: set only one of Formula or Paragraph")
}

When it happens

Trigger: Calling AddChart with Chart{Title: ChartTitle{Formula: "Sheet1!$A$27", Paragraph: []RichTextRun{{...}}}} — both fields populated in the same ChartTitle struct.

Common situations: Merging two example snippets (formula title and rich-text title) into one options struct; copy-pasting config where a previous Paragraph was left in place while adding a Formula link; generating charts from templates that set both.

Related errors

• ErrTransparency
• unsupported VBA project
• fill type value must be one of 'gradient' or 'pattern'
• fill color value must be an array of two colors for 'gradien
• fill shading value must be between 0 and 16 for 'gradient' t

AI-assisted analysis of qax-os/excelize@f2483381fb (2026-09-02). Data as JSON: /api/errors/22c4c7500043bd5d. Report an issue: GitHub.