Basic Examples (2) 

Identify elements of an array that are larger than 5:

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Identify elements that are greater than or equal to 3 but less than 7:

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Scope (5) 

Higher dimensional arrays are supported:

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Compare each row of a matrix with a different constant:

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Compare two arrays:

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BoolEval supports any expression that works with arithmetic and basic numerical operations:

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BoolEval works with images:

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Applications (3) 

Count the number of array elements that are greater than 0.3:

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Pick non-positive elements of an array:

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Process an array much faster than it would be possible using Select or Cases:

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Properties and Relations (3) 

BoolEval effectively threads comparisons over arrays, then converts truth values to 0 or 1:

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Literal truth values are also converted to 0s and 1s:

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Passing symbolic input to BoolEval reveals how it translates inequalities to UnitStep and logical operators to arithmetic ones:

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Possible Issues (4) 

Only those operators are processed which appear literally in the argument of BoolEval:

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Evaluate the argument explicitly using the Evaluate function to allow BoolEval to see the operators:

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BoolEval is optimized for performance, and does not check its arguments for correctness:

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The arrays in the argument must be numeric:

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Neat Examples (1) 

Estimate the value of π using Monte Carlo integration:

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