[0⎻⎺⎻x—x⎻x—⎼⎽_E_⎽⎼—x⎻⎺‾E‾⎺⎻x_⎽⎼—0(234)]
Inserting bracketed numbers throws the whole sparkline concept out the window.If terminal output is the use case here, why not use color when available? Zero crossings could be highlighted in blue, and out-of-bound clipping could be shown in red. Long sequences of zeroes could just be represented with a red line, or even empty space:
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Silence should be easy to spot, not crammed behind numbers! [0(512)]
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Which style would you find easier to understand at a glance?