 
            Set the value of a type rational tag.
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AT_ERRCOUNT ACCUAPI IG_ISIS_tag_set_rational(
        HISISDRV hDriver,
        AT_MODE nTag,
        WORD wIndex,
        LPAT_ISIS_RAT lpValue
);
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| Name | Type | Description | 
|---|---|---|
| hDriver | HISISDRV | The handle to the driver. | 
| nTag | AT_MODE | Specifies the type rational tag to set. | 
| wIndex | WORD | Specifies which element to set. wIndex must be greater than or equal to zero and at most one less than the value returned by IG_ISIS_tag_get_length. | 
| lpValue | LPAT_ISIS_RAT | Specifies the value to which to set nTag's specified element. | 
Returns the number of ImageGear errors that occurred during this function call. If there are no errors, the return value is IGE_SUCCESS.
This function does not process image pixels.
The IG_ISIS_tag_set_rational function sets the value of the specified type rational tag's specified element to the given value.
Use IG_ISIS_tag_set_rational to set the specified element of nTag to the rational value given in lpValue.IG_ISIS_tag_set_rational will not automatically increase the number of elements in a tag. You must use IG_ISIS_tag_set_length before calling IG_ISIS_tag_set_rational to do this.
The following example sets the rational value of IG_ISIS_TAG_RESOLUTION:
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| AT_ISIS_RAT ratValue; ratValue.Num = 300; ratValue.Denom = 1;IG_ISIS_tag_set_rational(hDriver, IG_ISIS_TAG_XRESOLUTION, 0, &ratValue); | |