A vector-based lookup looks for a value in a row or column area (called a vector) and then returns a value in the same position in another row or column area. If you want to specify a range that contains values to match, use this form of lookup function. The syntax of vector form is 1. LOOKUP (lookup _ value，lookup _ vector，result _ vector)。 Lookup _ value is the value that Lookup searches in the first vector. Lookup_value can be a number, text, logical value or a name or reference representing a value. Lookup_vector is an area that contains only one row or one column. Values in lookup_vector can be text, numbers, or logical values. 2. Important: The values in lookup_vector must be arranged in ascending order. For example, -2,-1, 0, 1, 2 or A-Z is false or true. Otherwise, the value returned by LOOKUP may be incorrect. Uppercase and lowercase text are equivalent. Result_vector is a region containing only one row or one column. It must be the same size as lookup_vector. 3. Please note that if LOOKUP cannot find lookup_value, it will match the maximum value in lookup_vector that is less than or equal to lookup_value. If LOOKUP_value is less than the minimum value in LOOKUP_vector, lookup will return #N/A error value. Examples of searching in the form of array Searching in the form of array finds the specified value in the first row or column of array, and then returns the value in the same position in the last row or column of array. Use this form of lookup if the value you want to match is in the first row or column of the array. The syntax LOOKUP (lookup _ value, array) in the form of array lookup _ value is the value found in the array. Lookup_value can be a number, text, logical value or a name or reference representing a value. If LOOKUP cannot find lookup_value, it will use the largest value in the array that is less than or equal to lookup_value. If LOOKUP_value is less than the minimum value in the first row or column (depending on the array dimension), LOOKUP will return a #N/A error value. An array is a range of cells containing text, numbers, or logical values for comparison with lookup_value. Searching in array form is similar to HLOOKUP function and VLOOKUP function. The difference is that HLOOKUP searches LOOKUP_value in the first row, VLOOKUP searches in the first column, and LOOKUP searches according to the dimension of the array. If the width of the area covered by the array is greater than the height (there are more columns than rows), LOOKUP will search lookup_value in the first row. If the area covered by the array is square or the height is greater than the width (the number of rows is greater than the number of columns), LOOKUP will search in the first column. When using HLOOKUP and VLOOKUP, you can index down or cross-index, but LOOKUP always selects the last value in a row or column. Important: The values in the array must be arranged in ascending order. For example, -2,-1, 0, 1, 2 or A-Z is false or true. Otherwise, the value returned by LOOKUP may be incorrect. Uppercase and lowercase text are equivalent.