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function is not described

wp_update_category() WP 2.0.0

Aliases wp_insert_category() with minimal args.

If you want to update only some fields of an existing category, call this function with only the new values set inside $catarr.

No Hooks.

Return

Int/true/false. The ID number of the new or updated Category on success. Zero or FALSE on failure.

Usage

wp_update_category( $catarr );
$catarr(array) (required)
The 'cat_ID' value is required. All other keys are optional.

Code of wp update category: wp-admin/includes/taxonomy.php VER 5.0.3

<?php
function wp_update_category($catarr) {
	$cat_ID = (int) $catarr['cat_ID'];

	if ( isset($catarr['category_parent']) && ($cat_ID == $catarr['category_parent']) )
		return false;

	// First, get all of the original fields
	$category = get_term( $cat_ID, 'category', ARRAY_A );
	_make_cat_compat( $category );

	// Escape data pulled from DB.
	$category = wp_slash($category);

	// Merge old and new fields with new fields overwriting old ones.
	$catarr = array_merge($category, $catarr);

	return wp_insert_category($catarr);
}