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Right-click a Numeric function and select Properties from the shortcut menu to display this dialog box.

Appearance

Use this tab to specify which elements of the object are visible.

• Label Visible—Displays the owned label for the object and enables the Label Text text box so you can edit the label. You use the label to identify the object on the front panel and block diagram.
• Label Text—Text to use for the label.

Output Configuration

Use this tab to specify the configuration of the output of a numeric function.

• Representation—Sets the representation of the output value.
• Adapt to source—Sets whether the configuration settings for the output value, such as Representation, adapt to the input values you wire to the function. If you wire fixed-point input values to the function, LabVIEW automatically sets the Fixed-Point Configuration settings to avoid data loss, if possible.

  , this option does not appear for the Boolean Array To Number and To Fixed-Point functions.

• Fixed-Point Configuration—Sets the configuration settings for a fixed-point output value. Set Representation to Fixed-point (FXP) to enable these options.
• Rounding mode—Sets how the function handles quantization conditions. Set Representation to Fixed-point(FXP) to enable this option. You can select from the following options:
  • Truncate—LabVIEW rounds the value down to the nearest value that the output type can represent. LabVIEW discards the least significant bits of the value. This rounding mode has the lowest impact on performance, but also produces the least accurate values.
    
    For example, if s<x<t, LabVIEW sets x to equal s.
  • Round Half-Up—LabVIEW rounds the value to the nearest value that the output type can represent. If the value lies exactly between two such values, LabVIEW rounds the value up to the higher of the two by adding half a least significant bit to the value and then truncating the value. This rounding mode has a larger impact on performance than Truncate, but it produces more accurate output values.
    
    For example, if s<x<t, set x to equal the closer of s or t. If x is exactly between s and t, select t.
  • Round Half-Even—(Default) LabVIEW rounds the value to the nearest value that the output type can represent. If the value lies exactly between two such values, LabVIEW checks the bit of the value that becomes the least significant bit after rounding. If the bit is 0, LabVIEW rounds the value to the lower of the two values that the output type can represent. If the bit is not 0, LabVIEW rounds the value to the higher of the two values. This rounding mode has the largest impact on performance, but it produces more accurate output values than Truncate and neutralizes the bias towards higher values that can occur when you perform multiple Round Half-Up operations.
    
    For example, if s<x<t, LabVIEW sets x to equal the closer of s or t. If x is exactly between s and t, LabVIEW selects s if the least significant bit after rounding is 0. LabVIEW selects t if the least significant bit after rounding is not 0.
• Overflow mode—Sets how the function handles overflow conditions. Set Representation to Fixed-point(FXP) to enable this option. You can select from the following options:
  • Wrap—If the value is greater than the Maximum value in the Range, LabVIEW coerces the value to the specified Maximum. If the value is less than the Minimum value in the Range, LabVIEW coerces the value to the specified Minimum.
  • Saturate—If the value is outside the specified Range, LabVIEW discards significant bits of the value until the value falls within the Range. If you select this option, LabVIEW recomputes the Range based on the Encoding settings you specify.
• Encoding—Sets the binary encoding settings for a fixed-point output value.
• Signed—Sets whether the fixed-point output value is signed.
• Word length—Sets the number of bits that LabVIEW uses to represent all the possible fixed-point output values.
• Integer word length—Sets the number of integer bits, or the number of bits to shift the binary point to reach the most significant bit, for all the possible fixed-point output values. Integer word length can be larger or smaller than Word length and can be positive or negative.
• Range—Sets the desired range for a fixed-point output value.

  Note  The fields you use to specify these values display the values in double-precision floating-point representation, so the precision of Maximum, Minimum, and Desired delta might not be exact in terms of fixed-point representation. However, the deviation is very small.

• Minimum—Sets the minimum value for the fixed-point data range.
• Maximum—Sets the maximum value for the fixed-point data range.
• Desired delta—Specifies the maximum distance between any two sequential numbers in the fixed-point data range.