tui-cs/Terminal.Gui · error · ArgumentException

Number of values must match the number of bars per category

Error message

Number of values must match the number of bars per category

What it means

AddBars adds a cluster of bars to a MultiBarSeries. Each cluster must contain exactly one value per bar-in-category (the count passed to the constructor). A mismatched values array would leave some bars empty or index out of range, so it is rejected.

Source

Thrown at Terminal.Gui/Views/GraphView/MultiBarSeries.cs:81

    /// <param name="drawBounds"></param>
    /// <param name="graphBounds"></param>
    public void DrawSeries (GraphView graph, Rectangle drawBounds, RectangleF graphBounds)
    {
        foreach (BarSeries bar in _subSeries)
        {
            bar.DrawSeries (graph, drawBounds, graphBounds);
        }
    }

    /// <summary>Adds a new cluster of bars</summary>
    /// <param name="label"></param>
    /// <param name="fill"></param>
    /// <param name="values">Values for each bar in category, must match the number of bars per category</param>
    public void AddBars (string label, Rune fill, params float [] values)
    {
        if (values.Length != _subSeries.Length)
        {
            throw new ArgumentException (@"Number of values must match the number of bars per category", nameof (values));
        }

        for (var i = 0; i < values.Length; i++)
        {
            _subSeries [i]
                .Bars.Add (
                           new (
                                label,
                                new (fill),
                                values [i]
                               )
                          );
        }
    }
}

View on GitHub (pinned to 2e47b11478)

Solutions

1. Pass exactly numberOfBarsPerCategory values in every AddBars call.
2. Pad or truncate the values array to match _subSeries.Length before calling.
3. Store numberOfBarsPerCategory and assert values.Length matches it before AddBars.

Example fix

// before
var s = new MultiBarSeries(3, 1f, 0.5f);
s.AddBars("Q1", '#', 1f, 2f); // only 2 of 3
// after
s.AddBars("Q1", '#', 1f, 2f, 3f);

if (values.Length != series.SubSeries.Count)
    Array.Resize(ref values, series.SubSeries.Count);
series.AddBars (label, fill, values);

static bool ValuesMatchBars (MultiBarSeries s, float[] v) => v.Length == s.SubSeries.Count;

When it happens

Trigger: series.AddBars("Q1", '#', 1f, 2f) on a series created with numberOfBarsPerCategory=3; passing fewer or more values than the constructor specified.

Common situations: Changing numberOfBarsPerCategory in the constructor but forgetting to update AddBars call sites; data sourced from an array whose length varies at runtime.

Related errors

• Number of colors must match the number of bars
• OmitClassName is not allowed when Scope is AppSettingsScope
• Provided text is too short to be any known color format.
• The text provided was null or empty.
• The text provided consisted of only whitespace characters.

AI-assisted analysis of tui-cs/Terminal.Gui@2e47b11478 (2026-08-13). Data as JSON: /api/errors/934fd58c57fb496f. Report an issue: GitHub.